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The XVIII International Conference on Topics in Astoparticle and Underground Physics (TAUP2023) is organized by the Institute of High Energy Physics (HEPHY) of the Austrian Academy of Sciences, the University of Vienna, the Technische Universität Wien, the University of Innsbruck and the Comenius University Bratislava.
The biennial TAUP series covers recent experimental and theoretical developments in astroparticle physics by invited plenary review talks, parallel workshop sessions of invited and contributed presentations, and poster sessions.
Notes:
Next-generation cosmological experiments will considerably improve our understanding of the Univers, by providing extremely precise measurements of cosmological observables.
Observational programs like the ground-based Simons Observatory or CMB-Stage 4, together with the JAXA satellite LiteBIRD, will characterize the cosmic microwave background (CMB) anisotropies in temperature and polarization over a wide range of scales, aiming at detecting the gravitational waves generated during inflation. Galaxy surveys like Euclid (launched on July 1st, 2023), Vera Rubin Observatory and Nancy Roman Telescope will reconstruct the matter distribution in the Universe and shed light on dark matter, dark energy and the nature of gravity. I will review these observational efforts, and discuss their relevance for cosmological measurements of neutrino masses.
I will provide a review of Cosmic Inflation, currently our most compelling explanation for the initial conditions of the universe. Cosmic inflation predicts the existence of small initial fluctuations in the curvature field distributed according to a Gaussian statistics, and responsible for both the large-scale structure of the universe and the observed anisotropies within the cosmic microwave background. My talk will focus on the recent progress to address the generation of primordial non-Gaussianity during cosmic inflation. If detected by forthcoming cosmological surveys, such deviations could offer invaluable insights into the dynamics and interactions of various fields during inflation.
Detecting low-energy neutrinos from astronomical objects and the Earth is an essential means of accessing information about the interiors of stars and planets.
Detecting neutrinos in the Si-burning phase of a galactic supernova will allow us to predict the explosion. Disseminating the direction of the arrival of neutrinos from galactic supernova explosions to observatories will be crucial for multi-messenger astronomy. Detection of neutrinos from past supernova explosions (Diffuse Supernova Neutrino Background) will provide a picture of the average supernova explosion and the history of black holes and neutron star formations.
Observations of solar neutrinos remain essential for understanding the Sun itself, including determining the metallicity of the Standard Solar Model. It is also crucial to determine the parameters of θ12 and Δm12 through solar neutrino oscillations, and the "up-turn" of the solar neutrino survival probability can be used to verify the MSW effect and the Non-standard Neutrino Interaction.
Decays of radioactive elements in the Earth's interior generate geo-neutrinos and heat. By measuring the geo-neutrinos on the Earth's surface, the amount of heat radiated from the Earth's interior can be directly determined, and it is expected that the mantle convection structure and chemical composition of the Earth's interior can be elucidated.
The status and prospects of the experiments observing those neutrinos are reviewed.
The Simons Observatory (SO) is a cosmic microwave background (CMB) survey experiment located in the Atacama Desert in Chile at an elevation of 5200 meters, consisting of an array of three 0.42-meter small aperture telescopes (SATs) and one 6-meter large aperture telescope (LAT). SO will make accurate measurements of the CMB temperature and polarization spanning six frequency bands ranging from 27 to 285 GHz, fielding a total of 60,000 detectors covering angular scales between one arcminute to tens of degrees. In this talk we focus on the SATs, which are tailored to search for primordial gravitational waves, with the primary science goal of measuring the primordial tensor-to-scalar ratio r at a target level of 𝜎(r) ≈ 0.003. We discuss the design drivers, scientific impact, and current deployment status of the three SATs, which are scheduled to start taking data in the coming year. The SATs aim to map 10% of the sky at a 2 µK-arcmin noise level observing at Mid-Frequencies (93/145 GHz), with additional Ultra-High-Frequency (225/285 GHz) and Low-Frequency (27/39 GHz) targets to yield galactic foreground-subtracted measurements.
Although one of the two namesakes of the LCDM cosmological model, the hypothesis of cold dark matter existence still chiefly relies on its gravitational effects, whilst both direct and indirect detection via non-gravitational signatures have not yet been achieved.
Weakly interacting massive particles (WIMP) are a candidate cold relic with a mass of 1-1000 GeV: they might then annihilate or decay in γ photons and contribute to the unresolved gamma ray background (UGRB) detected by experiments such as Fermi – LAT. Even if dominated by an isotropic shot noise component, such emission should be more tightly tracing the LSS compared to astrophysical sources also present in the UGRB.
The angular cross-correlation power spectrum with galaxies might enhance such anisotropy, with an indirect detection thus translating into measuring a residual signal after substraction of the astrophysical contribution.
Typical signal shapes and amplitudes can be defined in terms of multipoles, redshift, energy and mass range of the probed halos and gauged to sensitivity and resolution of present and future instruments. Within this general framework, we present a weighting scheme of the galaxy tracer which proved effective in enhancing the anisotropic contribution of other shot noise – dominated LSS tracers, such as cosmic rays and gravitational waves, and assess its efficiency in terms of signal to noise ratio and constraining power on the WIMP mass and its annihilation or decay cross sections.
Dark matter energy injection in the early universe modifies both the ionization history and the temperature of the intergalactic medium.
In this work, we improve the CMB bounds on sub-keV dark matter and extend previous bounds from Lyman-$\alpha$ observations to the same mass range, resulting in new and competitive constraints on axion-like particles (ALPs) decaying into two photons.
The limits depend on the underlying reionization history, here accounted self-consistently by our modified version of the publicly available DarkHistory and CLASS codes. Future measurements such as the ones from the CMB-S4 experiment
may play a crucial, leading role in the search for this type of light dark matter candidates.
If the temperature of the hot thermal plasma in the Early Universe was within a few orders of magnitude of the quantum gravity scale, then the hoop conjecture predicts the formation of microscopic black holes from particle collisions in the plasma. These black holes may evaporate and produce the dark matter relic abundance observed today for a wide variety of dark matter masses. We study the production of dark matter in standard cosmology and in the scenario of low-scale quantum gravity such as large extra dimensions. In the former case black holes evaporate instantly, while in the latter case dark matter may accrete and become macroscopic, leading to rich phenomena in the late Universe.
Inflationary models with solid described through a triplet of fields with homogeneous and isotropic properties are consistent with observations [1] and at the same time predict unique nonlinear properties of primordial perturbations [2]. A problematic feature is the possibility of superluminal propagation of perturbations, which considerably restricts the parameter space of studied models. Assuming constant pressure to energy ratio w, this superluminality is avoided for w ≤ (19-8√7) ≈ -0.722, and the behavior of scalar, vector, and tensor perturbations considerably differs from the case with perfect fluid [3]. This illustrates possible challenges with comparing the observational data to models similar to solid inflation. In my talk, I plan to elaborate on distinctive features of solid-like matter models related to my latest research.
[1] S. Endlich et al., JCAP 10 (2013) 011, arXiv:1210.0569 [hep-th].
[2] P. Mészáros, JCAP 09 (2019) 048, arXiv:1905.03544 [gr-qc].
[3] P. Mészáros, arXiv:2302.14480 [gr-qc].
The SPLENDOR (Search for Particles of Light Dark Matter with Narrow-gap Semiconductors) experiment is a search for light dark matter via the electron-recoil interaction channel, taking advantage of novel single-crystal narrow-bandgap (order 10-100 meV) semiconductors. Synthesized within the collaboration, the properties of these designer materials imply low dark counts when operated as ionization detectors at cryogenic temperatures. Using a readout scheme based on low-noise cryogenic high electron mobility transistors (HEMTs), the experiment is on track to achieve O(1) electron-hole pair resolution. This provides an excellent opportunity to probe new light dark matter parameter space: down to sub-MeV masses for fermionic dark matter and sub-eV masses for bosonic dark matter. This talk will review the multidisciplinary R&D behind SPLENDOR, discuss the current status of the experiment, and present projected sensitivities for planned dark matter searches operated both above- and below-ground.
This work was supported by the U.S. Department of Energy through the Los Alamos National Laboratory. Los Alamos National Laboratory is operated by Triad National Security, LLC, for the National Nuclear Security Administration of U.S. Department of Energy (Contract No. 89233218CNA000001). Research presented in this presentation was supported by the Laboratory Directed Research and Development program of Los Alamos National Laboratory under project number 20220135DR.
Leading cosmological surveys and models provide strong indications for cold Dark Matter (DM) being a major constituent of our Universe. However, direct observation of the hypothesized galactic flux of DM particles streaming through the Earth remains an open quest.
The SuperCDMS collaboration is currently constructing a Generation-2 direct DM search experiment at the SNOLAB underground facility in Sudbury, Canada. It will employ two types of state-of-the-art cryogenic Ge and Si detectors capable of detecting sub-keV energy depositions. The unique mix of target substrates and detector technologies allows for a simultaneous study of intrinsic and external backgrounds as well as exploring the DM mass range below 10 GeV/$c^2$ with world-leading sensitivity.
In order to extend the sensitivity to lower DM masses, a precise understanding of the detector response down to the semiconductor bandgap energy is required. This effort is driven by a comprehensive prototype testing program and the development of a sophisticated Detector Monte-Carlo to guide the data analysis and model building.
This talk will present an overview of our detector technology and recent milestones towards science operation with SuperCDMS at SNOLAB.
SuperCDMS is a direct detection dark matter (DM) experiment currently being constructed at the SNOLAB underground laboratory in Sudbury, Canada. A complementary approach of cryogenically cooled Ge and Si crystals together with different sensor designs enables a broadband DM search for particles with masses $\le$ 10 GeV/$c^2$.
In order to reach this sensitivity, it is crucial to understand the background composition of the measured energy spectra. For this purpose, GEANT4 based simulations are performed in which all detector, cryostat, shielding and structural components are contaminated according to their known radioactive impurities from screening measurements. The subsequent decays and particle emissions are propagated through the setup and can create energy deposits in the sensitive Ge and Si crystals. Simulations for components located far away from the detectors are very inefficient and even with an extremely high number of primary events on the order of $10^{12}$ the detected energy spectra are lacking in statistics which propagates into large uncertainties in the background composition.
GEANT4 offers a mechanism called Importance Biasing which can increase the amount of detector hits by orders of magnitude for the same number of primary events. This talk will present the challenges of implementing Importance Biasing in our GEANT4 application and will discuss the achieved efficiency boost of the respective background simulations.
SuperCDMS is constructing its second-generation experiment at SNOLAB to detect dark matter candidates with masses $\leq$ 10 GeV/$c^2$ using pure Ge and Si detectors operated at cryogenic temperature. These detectors are of two types. The interleaved Z-sensitive Ionization and Phonon (iZIP) detectors can differentiate between nuclear and electron recoils, providing effective background rejection, while the High Voltage (HV) detectors use high voltage bias to attain excellent energy resolution and low energy threshold. To analyze dark matter search data, detailed energy calibrations of these detectors are necessary. Unlike Ge detectors, in Si detectors, we do not have activation lines that can be used in low energy calibration ($\leq$ $\mathcal O$(keV)). However, Si Compton steps can serve as an alternative for energy calibration in this region. The SuperCDMS Si HVeV detectors, with their energy resolution of $\mathcal O$(eV) and energy thresholds of $\mathcal O$(10 eV), are the perfect instruments to study the Compton steps. This work aims to investigate the K shell and L shell Compton steps at 1.8 keV and 0.1 keV, respectively, for Si HVeV detectors and compare them with calibration derived from optical photons. The understanding of Compton steps for these detectors will aid in calibrating the larger SuperCDMS SNOLAB Si HV detectors. In this conference, we will present the current status of the Compton step calibration analysis for Si HVeV detectors.
DAMIC-M employs skipper charged-coupled devices (CCDs) with detection threshold of just a few ionization charges to search for low-mass dark matter candidates. An important component of the background comes from small-angle Compton scatters of environmental gamma-rays which must thus be characterized down to O(10 eV) energy. We used an Am-241 source to measure gamma-ray scattering on silicon atomic shell electrons in a skipper CCD with single-electron resolution. The measurement found notable differences between data and theoretical expectations in the L-shell energy region (<150 eV). We also present preliminary data on a nuclear recoil ionization efficiency measurement in Si down to few ionization charges, obtained with a skipper CCD exposed to low-energy neutrons (<24 keV) from a SbBe photoneutron source. Lastly, we report on a novel method under exploration to identify nuclear recoils through the associated production of lattice defects in the silicon.
The electron-counting capability of the skipper-CCDs has enabled world leading searches for low mass DM-electron scattering in experiments with less than 100g active mass (SENSEI and DAMIC-M). Oscura is the ongoing effort to develop a 10 kg skipper-CCD experiment for dark matter search. In this talk I will discuss the current status and plans for the Oscura experiment, including the performance of the prototype sensors and the plans for early science.
This talk is aimed at showing how to consistently incorporate the impact of dark matter subhalos in predictions for indirect dark matter searches, from semi-analytical methods. These have several advantages over blind extrapolations of cosmological simulation results, often used in this context, as they self-consistently account for the dynamical properties of host halos. Examples will be shown for predictions of subhalo detection in the Milky Way (in gamma rays), as well as prospects for Sommerfeld-enhanced signals from dwarf galaxies or clusters. This talk is based on a series of papers (some still to be released), e.g. 2201.09788, 2203.16491, 2203.16440, 2007.10392.
The elastic scattering between dark matter (DM) and radiation can potentially explain small-scale observations that the cold dark matter faces as a challenge, as damping density fluctuations via dark acoustic oscillations in the early universe erases small-scale structure. We study a semi-analytical subhalo model for interacting dark matter with radiation, based on the extended Press-Schechter formalism and subhalos' tidal evolution prescription. We also test the elastic scattering between DM and neutrinos using observations of Milky-Way satellites from the Dark Energy Survey and PanSTARRS1. This talk is based on arXiv: 2305.01913.
It has been argued that Globular Clusters can be originated as dwarf galaxies whose dark matter is then stripped through tidal interactions with the host galaxy. If that is the case, one can argue that, using compacts stars such as white dwarfs, and assuming that a dark matter component survived the stripping, it is possible to place constrains on dark matter interactions such as annihilation and scattering through observables such as the temperature of the stars. One important ingredient, is the dark matter density present in the GC, so far, only semi-analytical methods have been used to provide such value. In this work we revisit those limits using the stellar kinematics of the GC to place constraints on the dark matter density.
In this talk, I will present updated constraints on 'light' dark matter (DM) particles with masses between 1 MeV and 5 GeV. In this range, we can expect DM-produced $e^\pm$ pairs to upscatter ambient photons in the Milky Way via Inverse Compton, and produce a flux of X-rays that can be probed by a range of space observatories. Using diffuse X-ray data from XMM-Newton, INTEGRAL, NuSTAR and Suzaku, we compute the strongest constraints to date on annihilating DM for 200 MeV < $m_{DM}$ < 5 GeV and decaying DM for 100 MeV < $m_{DM}$ < 5 GeV. I will also discuss possible future developments of these results and this technique.
We consider threshold effects of thermal dark matter (DM) pairs (fermions and antifermions) interacting with a thermal bath of dark gauge fields in the early expanding universe. Such threshold effects include the processes of DM pairs annihilating into the dark gauge fields (light d.o.f.) as well as electric transitions between pairs forming a bound state or being unbound but still feeling non-perturbative long range interactions (Sommerfeld effect). We scrutinize the process of bound-state formation (bsf) and the inverse thermal break-up process (bsd), but also (de-)excitations, providing a thermal decay width due to the thermal bath. We compute the corresponding observables by exploiting effective-field-theory (EFT) techniques to separate the various scales (the mass of the particles M, the momenta Mv, the energies Mv^2, as well as thermal scales: the temperature T, the Debye mass m_D), which are intertwined in general. To do so we make use of the so-called non-relativistic EFT (NREFT) as well as potential non-relativistic EFT (pNREFT) at finite T. These processes play an important role for a quantitative treatment of the dynamics of the relevant d.o.f. at the thermal freeze-out regime and the corresponding observables appear in the relevant evolution equations, from which we eventually determine the relic energy density of DM.
The cosmic-ray experiment AMS-02 has reported the possible detection of $\sim 10$ anti-helium events. Conventional production mechanisms struggle to explain the similar fluxes observed for both isotopes ${}^4\overline{\mathrm{He}}$ and ${}^3\overline{\mathrm{He}}$. In this talk, I discuss how these species could be created through "anti-nucleosynthesis" occurring in fireballs of standard model antiquarks, leptons, and photons expanding with a relativistic bulk velocity. Such fireballs may be initiated by collisions between heavy composite states in the dark sector that carry negative baryon number. Since the fireballs are thermalized, our explanation has the distinction of being agnostic to the particular dark matter model employed. It has the additional advantage of naturally producing nuclei travelling relativistically with $\gamma \sim 10$, as observed.
We present the latest precision measurements of the electron flux based on 57 million electron events collected by the Alpha Magnetic Spectrometer on the International Space Station during first eleven years of operations. These results on cosmic-ray electrons in the energy range from 0.5 GeV to 2 TeV reveal new features that are crucial for providing insights into their origins. Comparing the behavior of the electron spectrum with the spectrum of positrons measured by AMS, we found that at lower energies below few hundred GeV these two spectra have distinctly different magnitudes and energy dependences. This shows that at lower energies these two species of cosmic ray particles have very different origins. At high energies we observe that the source of high energy positrons, which has either particle or astrophysical origin, also manifests itself in the electron spectrum. This is the first indication of the existence of identical charge symmetric source term both in the positron and in the electron spectra and, as a consequence, the existence of new physics.
Cosmic-ray (CR) antiparticles have the potential to reveal signatures of unexpected astrophysical processes and new physics. Recent CR experiments have provided accurate measurements of the positron flux, revealing the so-called positron excess at high energies. However, the uncertainties related to the modelling of the positron flux are still too high, significantly affecting our models of positron emission from pulsars and current dark matter searches.
In this talk, I’ll show state-of-the-art predictions of CR positrons at Earth, focusing on the treatment of the secondary production of these particles. We show new cross sections derived from the FLUKA code and discuss the uncertainties related to cross sections, as well as to the other main sources of uncertainties affecting our predictions of CR positrons. Finally, we comment on the impact of these uncertainties in the evaluation of the positron emission from nearby pulsars and current WIMP searches with positrons.
We report the latest results of primary cosmic ray proton, helium, carbon, oxygen, neon, magnesium, silicon, sulfur and iron fluxes based on the data collected by the Alpha Magnetic Spectrometer experiment on the international space station during 11.5 years operation. The proprieties of primary cosmic rays will be discussed and systematic comparison with the latest GALPROP cosmic ray model is presented.
We present the latest precision AMS measurements of the fluxes of all charged cosmic elementary particles, positrons, electrons, protons, and antiprotons based on the first 11 years of data collected on the International Space Station. These unique results, obtained with the same detector and with unprecedented precision in the uncharted energy range, provide precise experimental information and reveal new properties of cosmic charged elementary particles. In the absolute rigidity range of 60 to 525 GV, the antiproton-to-proton flux ratio is constant, and the antiproton flux and proton flux have identical rigidity dependence. This behavior indicates an excess of high-energy antiprotons compared with secondary antiprotons produced from the collision of cosmic rays. More importantly, from 60 to 525 GV, the antiproton flux and positron flux also show identical rigidity dependence. The positron-to-antiproton flux ratio is independent of energy and its value is determined to be a factor of 2 with percent accuracy. This unexpected observation indicates a common origin of high-energy antiprotons and positrons in the cosmos.
The space-based DAMPE (DArk Matter Particle Explorer) detector has been taking data since its successful launch in December 2015. Its main scientific goals include the indirect search for dark matter signatures in the cosmic electron and gamma-ray spectra, the measurements of galactic cosmic ray fluxes from tens of GeV up to hundreds of TeV and high energy gamma ray astronomy above a few GeV.
The measurements of galactic cosmic ray spectra will be reported, those being fundamental tools to investigate the mechanisms of acceleration at their sources and propagation through the interstellar medium. In particular, results on proton and helium, which revealed new spectral features, will be described.
Ongoing analyses on light, medium, and heavy mass nuclei will be outlined, together with results on secondary-to-primary flux ratios.
Finally, the latest results on gamma-ray astronomy and dark matter search will be also summarized.
The HERD (High Energy cosmic-Radiation Detector) experiment is a future space based experiment for the direct detection of high energy cosmic rays. It will be installed on the Chinese Space Station in 2026. The detector is based on a 3D, homogeneous, isotropic, deep and finely segmented calorimeter, surrounded by multiple sub-detectors for charge, timing and track measurement. Thanks to its innovative geometry the detector will be capable to detect particles from all directions, having a large geometric acceptance. This, together with a good energy resolution, will provide the detector an effective geometric factor about one order of magnitude larger than that of current space experiments for protons and electrons detection. Thanks to this feature, the HERD experiment will measure cosmic rays proton flux up to 1 PeV, performing the first direct measurement of the cosmic ray knee region. In addition, HERD will measure electron+positron flux up to tens of TeV, and will search for possible indirect signals of dark matter and local sources of electrons and positrons. These energy limits, for protons and electrons, will be more than one order of magnitude higher than that of the current space experiments. Moreover, measuring high energy photons HERD will search for sources of high energy cosmic rays and for indirect signals of dark matter.
In this talk we want to introduce the HERD experiment, with its innovative features, and the potential of its future measurements.
The recent 4.2$\sigma$ evidence of TeV neutrino emission from the
nearby active galaxy NGC 1068 observed by IceCube suggests that
AGN could make a sizable contribution to the diffuse high-energy
astrophysical neutrino flux. The absence of TeV gamma rays from
NGC 1068 indicates neutrino production in the innermost region of the
AGN. Disk-corona models predict a correlation between neutrinos and
keV X-rays in Seyfert galaxies, a subclass of AGN to which NGC 1068
belongs. In this talk, using 10 years of IceCube muon neutrino events,
we report the results of searches for neutrino emission from X-ray bright Seyfert galaxies.
This talk will focus on the latest observations in the study of neutrinos from Seyfert galaxies based on recent results from the IceCube observatory. We will discuss the current understanding of the underlying models that explain the observed neutrino fluxes and explore the implications for the study of high-energy astrophysics. Additionally, we will highlight the prospects for neutrino observations using the P-ONE future experiment and discuss how these measurements could further our understanding of these enigmatic objects.
We use the recent discovery of the first steady-state source of high-energy astrophysical neutrinos by IceCube, NGC 1068, to probe the lifetime of neutrinos. By searching for specific features in the energy spectrum of neutrinos, we seek to detect the decay of neutrinos during their journey to Earth. Although the current event rates and uncertainties in the predicted neutrino flux from NGC 1068 limit our ability to identify novel physics signatures in the data and constrain the neutrino lifetime significantly, longer exposures and joint observations from upcoming neutrino telescopes and multi-messenger observations of NGC 1068 will improve our sensitivity to neutrino decay and other novel physics signatures. Furthermore, we demonstrate how we can use the flavour information of neutrinos inferred from the observation of cascade-like events from NGC 1068 in in-water neutrino detectors such as KM3NeT to establish more robust constraints on the neutrino lifetime, independently of the spectral shape of the neutrino flux emitted at the source.
In summary, the detection of high-energy astrophysical neutrinos from NGC 1068 provides a unique opportunity to probe the neutrino lifetime and investigate novel physics signatures. Our findings suggest that longer exposures and joint efforts with other telescopes will enable us to gain a deeper understanding of neutrino decay and other physics phenomena in the near future.
Though their imprint upon the CMB and large-scale structure of the universe remains to this day, Big Bang relic neutrinos (the CνB) have never been directly observed. This remains an outstanding test of the Standard Model in ΛCDM cosmology and would provide the earliest picture of the universe at only 1 second after the Big Bang. PTOLEMY aims to make the first direct observation of the CνB by resolving the β-decay endpoint of atomic tritium. The concept relies upon amassing a target of atomic tritium, developing RF-based trigger and tracking, an EM transverse drift filter, and a cryogenic micro-calorimeter - each of which present novel R&D challenges. A prototype will soon be based at LNGS. Intermediate measurements will be made of the lowest neutrino mass ahead of CνB physics runs set to begin in the 2030s.
We discuss the phenomenology of neutrino decoupling in the early universe, by summarising the details of the calculation in standard and non-standard scenarios. We quickly present the state-of-the-art calculation of the effective number of neutrino species in the early universe (Neff) in the three-neutrino case, which gives Neff=3.044, and show how the result can change when non-standard properties (non-standard interactions, non-unitarity) are considered.
The Double Chooz experiment has been at the forefront of accurately measuring the third neutrino mixing angle $\theta_{13}$. The experiment involves two identical liquid scintillator detectors at 400m and 1km baselines from the two N4 nuclear reactors in Chooz, France. To detect the neutrinos, the experiment uses the "total neutron capture" technique to measure the inverse beta decay (IBD) signature, which includes prompt positron annihilation and a delayed neutron capture signal on all possible isotopes available in the detector. The experiment's double detector setup, carefully considering all neutrino rates, energy spectral shapes, and inclusive backgrounds control model, allows for accurate measurement of $\theta_{13}$ and a precise characterization of the reactor flux. The latest results from the Double Chooz measurement and other physics searches, such as sterile neutrino oscillations, will be presented during this talk.
The recent observation of CNO solar neutrinos by Borexino (BX) has proven the high potential offered by large underground ultrapure liquid scintillators to disclose weak neutrino and antineutrino fluxes. Supernovae explosions, gamma-ray bursts, solar flares and Gravitational Waves (GW) are among the possible extra-terrestrial sources of neutrinos and antineutrinos. The extreme radiopurity of the BX detector has already allowed to get the best upper limits on all flavor fluences in the few MeV energy range from GRB, to set limits on the diffuse supernova antineutrino background in the unexplored energy region below 8 MeV and to get the strongest upper limits on fast radio bursts associated neutrino fluences in the 0.5−50 MeV energy range.
Recently, BX has searched for neutrino events in correlation with GW events for three runs from 2015 to 2020 using the BX data-set of the same periods. GW candidates originated by merging binaries of black holes, neutron stars and neutron star and black hole have been analysed separately, looking both for neutrino electron scattering and antineutrinos inverse beta decay interactions. The strongest upper limits on GW-associated neutrino and antineutrino fluences for all flavors ($\nu_{e}$,$\nu_{\mu}$,$\nu_{\tau}$) have been obtained in the (0.5 - 5.0) MeV neutrino energy range.
The talk is aimed to summarise BX results on the possible signals from astrophysical sources, with a particular focus on the new search for GW-associated neutrinos.
The decays of radioactive isotopes, uranium, thorium and potassium, inside the Earth generate a significant amount of radiogenic heat and contribute to the Earth’s heat budget. The abundance of these elements is a key parameter to reveal the planet’s geophysical activities. Geoneutrinos originated from these isotopes are unique probe to the composition, and thus, the amount of the radiogenic heat in the Earth. KamLAND has observed geoneutrinos from $^{238}$U and $^{232}$Th with 1 kt liquid scintillator for more than 18 years. The low-reactor period since 2011 enabled a spectroscopic measurement of geoneutrinos from $^{238}$U and $^{232}$Th by reducing the most significant background, reactor neutrino. The number of geoneutrino signal is estimated to be $116.6^{+41.0}_{−38.5}$, $57.5^{+24.5}_{−24.1}$ and $173.7^{+29.2}_{−27.7}$ from $^{238}$U, $^{232}$Th and $^{238}$U+$^{232}$Th, respectively. These correspond to geoneutrino flux of $14.7^{+5.2}_{−4.8}$, $23.9^{+10.2}_{−10.0}$ and $32.1^{+5.8}_{−5.3}$ $\times10^{5}$ cm$^{−2}$s$^{−1}$, respectively. The null-signal hypothesis is disfavored at 8.3$\sigma$ confidence level. This study yields the first constraint on the radiogenic heat contribution from $^{238}$U and $^{232}$Th individually, which is consistent to geochemical predictions based on the compositional analysis of chondrite meteorites.
published article : https://doi.org/10.1029/2022GL099566
Detecting geoneutrinos from potassium-40 decay in the Earth remains a challenge due to its decay endpoint being below the energy threshold of the inverse beta decay reaction on protons (used to detect U and Th geoneutrinos). Several nuclear targets for charged-current neutrino reactions do have lower threshold energies. Our study identified a particularly promising candidate, copper, and proposes Cu-doping a LiquidO opaque scintillator, an approach that is amenable to very high doping levels. Event topology information provided by LiquidO would offer powerful signal tagging and background rejection, both necessary for detecting K-40 geoneutrinos. The experimental concept, its methodology, discovery significance and backgrounds will be presented.
The Jiangmen Underground Neutrino Observatory (JUNO) is the state-of-the-art liquid-scintillator-based neutrino physics experiment, which is under construction in South China. Thanks to the 20 ktons of ultra-pure liquid scintillator (LS), JUNO will be able to perform innovative and groundbreaking measurements like the determination of neutrino mass ordering (NMO). The experiment has been constructed in a 700m underground laboratory, located about 52 km from both the Taishan and Yangjiang nuclear power plants. The JUNO central detector will be equipped with 17,612 20-inch photomultiplier tubes (PMTs) and 25,600 3-inch PMTs. JUNO CD energy resolution is expected to be better than 3% at 1 MeV and to have an absolute energy scale uncertainty better than 1% over the whole reactor antineutrino energy range. In addition, the JUNO experiment also has a satellite detector, the Taishan Antineutrino Observatory, to precisely measure the reactor antineutrino energy spectrum. Beyond NMO, JUNO will measure the three neutrino oscillation parameters with a sub-percent precision. Moreover, the JUNO experiment is also expected to have important physics reach with solar neutrinos, supernova neutrinos, geoneutrinos, atmospheric neutrinos, and searches for physics beyond the Standard Model such as nucleon decay. The detector construction is expected to be completed in 2023. In this talk, I will present the detector design and the installation status of the different JUNO subsystems.
The Accelerator Neutrino Neutron Interaction Experiment (ANNIE) is a Gadolinium-loaded water Cherenkov detector located in the Booster Neutrino Beam at Fermilab. Its primary physics goals are to measure the final state neutron multiplicity of neutrino-nucleus interactions for future long-baseline experiments and cross-sections relevant to atmospheric neutrino backgrounds for diffuse Supernova neutrino and proton decay searches. ANNIE is also a testbed for innovative new detection technologies. In early 2023, we temporarily installed a 365-kg acrylic vessel filled with water-based liquid scintillator (WbLS) in the main detector tank. This contribution will discuss the first WbLS data and basic properties of the WbLS determined in-situ in the experiment. It will highlight the benefits of WbLS as a target medium for future long-baseline experiments like THEIA.
In July 2020, we loaded 0.011% of gadolinium in Super-Kamiokande (SK) to enhance the detection efficiency of neutron signals and restarted the observation as the “SK-Gd experiment”. Now we are aiming to observe the Supernova Relic Neutrinos (SRNs) for the first time all over the world in the SK-Gd experiment. One of the main backgrounds in the SRNs search is the atmospheric neutrino-oxygen neutral-current quasielastic (NCQE) reactions. To discover the SRNs, it is essential to understand the neutrino-oxygen NCQE cross section and estimate the backgrounds more precisely. In this talk, we report the first result of the measurement of the neutrino-oxygen NCQE cross section using atmospheric neutrinos in the SK-Gd experiment and the consideration.
Precise knowledge of how neutrinos interact with matter is essential for measuring neutrino oscillations in long-baseline experiments. At T2K, the near detector complex measures neutrino interactions to constrain cross-section models for oscillation studies and to characterise the beam flux. The near detector complex provides a platform for performing neutrino-nucleon cross section measurements. The design of the ND280 near detector allows for a variety of cross section measurements on different targets to be performed. The additional WAGASCI near detector at a different off-axis angle features an increased Water/Carbon target ratio. Finally, the on-axis INGRID detector can be combined with ND280 and WAGASCI to measure the cross-section at different neutrino energies and to further constrain the nuclear models for different targets.
Recent cross section measurements from the near detector complex will be presented. The latest measurements of pion production in ND280, including measurements of transverse pion kinematics, and an improved analysis of coherent pion production making use of an anti-neutrino sample for the first time, will be shown. The first measurement of cross section without pions in the final state at the WAGASCI off-axis angle will be presented, as well as the first combined measurement of ND280 and INGRID allowing the first simultaneous measurement of cross-section at different neutrino off-axis angles, energies and different detectors on the same flux.
Monitored neutrino beams represent a powerful and cost effective tool to suppress cross section related systematics for the full exploitation of data collected in long baseline oscillation projects like DUNE and Hyper-Kamiokande. In the last years the NP06/ENUBET project has demonstrated that the systematic uncertainties on the neutrino flux can be suppressed to 1% in an accelerator based facility where charged leptons produced in kaon and pion decays are monitored in an instrumented decay tunnel. The collaboration is now working to provide the full implementation of such a facility at CERN in order to perform high precision cross section measurements at the GeV scale exploiting the ProtoDUNEs as neutrino detectors. This contribution will present the final design of the ENUBET beamline that allows to collect $\sim$10$^4$ $\nu_e$ and $\sim$6$\times$10$^5$ $\nu_{\mu}$ charged current interactions on a 500 ton LAr detector in about 2 years of data taking. The algorithms setup for high purity identification of charged leptons in the tunnel instrumentation will be described together with the framework for the assessment of the final systematics budget on the neutrino fluxes. We will also present the results of a test beam exposure at CERN-PS of a fully instrumented 1.65 m long section of the ENUBET instrumented decay tunnel. Finally the physics potential of the ENUBET beam with ProtoDUNE-SP and plans for its implementation in the CERN North Area will be discussed.
The DsTau experiment at CERN-SPS has been proposed to measure an inclusive differential cross-section of a Ds production with a consecutive decay to tau lepton in p-A interactions. A precise measurement of the tau neutrino cross section would enable a search for new physics effects such as testing the Lepton Universality (LU) of Standard Model in neutrino interactions. The detector is based on nuclear emulsion providing a sub-micron spatial resolution for the detection of short length and small “kink” decays. Therefore, it is very suitable to search for peculiar decay topologies (“double kink”) of Ds→τ→X. In 2022, the second physics run of the experiment was performed successfully. In this talk we discuss the physics potential of the experiment and present the analysis result of the pilot run data and the near-future plans.
SND@LHC is a compact experiment proposed to exploit the high flux of energetic neutrinos of all flavours from the LHC in a hitherto unexplored pseudo-rapidity region of 7.2 < 𝜂 < 8.4, complementary to all the other experiments at the LHC. The experiment is located 480 m downstream of IP1 in the unused TI18 tunnel. The detector is composed of a hybrid system based on an 830 kg target mass of tungsten plates, interleaved with emulsion and electronic trackers, also acting as an electromagnetic calorimeter, and followed by a hadronic calorimeter and a muon identification system. The configuration allows efficiently distinguishing between all three neutrino flavours, opening a unique opportunity to probe physics of heavy flavour production at the LHC in the region that is not accessible to ATLAS, CMS and LHCb. This region is of particular interest also for future circular colliders and for predictions of very high-energy atmospheric neutrinos. The physics programme includes studies of charm production, and lepton universality tests in the neutral sector. The detector concept is also well suited to searching for Feebly Interacting Particles via signatures of scattering in the detector target. The first phase aims at operating the detector throughout LHC Run 3 to collect a total of 250 fb−1. The experiment was installed in the TI18 tunnel at CERN and has collected its first data in 2022. A new era of collider neutrino physics has started.
Neutrino oscillation physics has now entered the precision era. In parallel with needing larger detectors to collect more data, future experiments further require a significant reduction of systematic uncertainties. In neutrino oscillation measurements at T2K, the systematic uncertainties related to neutrino interaction cross sections are currently dominant. To reduce this uncertainty, a significantly improved understanding of neutrino-nucleus interactions is required to better characterise nuclear effects.
The upgraded ND280 detector will consist of a totally active Super-Fine-Grained-Detector (Super-FGD) composed of 2 million 1 cm$^3$ scintillator cubes with three 2D readouts, two High Angle TPC (HA-TPC) instrumented with resistive MicroMegas, and six TOF planes. It will probe our knowledge of neutrino interactions due to its full polar angle acceptance and a much lower proton tracking threshold. Furthermore, neutron tagging capabilities, in addition to precision timing information, will allow the upgraded detector to measure neutron kinematics from neutrino interactions. Such improvements permit access to a much larger kinematic phase space and the analysis of transverse kinematic imbalances, to offer nuclear physics constraints for T2K analyses.
New reconstruction algorithms are being developed to benefit from the improved capabilities of the Super-FGD and of the HA-TPC and will be described in this talk together with the expected performances of the ND280 upgrade.
China Jinping underground Lab(CJPL) is the deepest underground laboratory with a rock overburden of 2400m. Now there are two phase in CJPL. CJPL-I is used for demonstration of CDEX, PandaX and low-background facility. A deep Underground and ultra-low Radiation background Facility for frontier physics experiments(DURF) was built in CJPL-II since Feb. 2020. The civil engineering of CJPL-II would be finished in Oct. 2023. Here the current status of the construction would be introduced in details. Noteworthy, the work about water-resistant and radon suppression during the construction and its effect by measurement would be illustrated. The status of development for ultra-low background facilities, such as Large Nitrogen vessel shielding device, large pure water tank shielding device, and assemble combine shielding device and ultra-low-background gamma spectrometers in CJPL-II, would be showed in the present. The prospects of dark matter experiments(CDEX, PandaX), Neutrinoless double beta decay experiments(target include Ge-76, Xe-136, Mo-100 and Se-82 et al), Nuclear Astrophysics experiment(JUNA), neutrino detect experiment(Qingting) and other experiment in CJPL-II is also introduced by this present.
Laboratori Nazionali del Gran Sasso (LNGS) of INFN are one the most important research center for astro-particle physics. Since the late 1980s, the role, results and international impact of LNGS have been constantly growing. Every year over a thousand scientists, from the most renowned universities and research institutions in the world, come to LNGS to participate in experiments.
The study of the properties of neutrinos, the search for dark matter and the understanding of the mechanisms underlying the functioning of stars are the main strands of the articulated LNGS research program.
Thanks to their size, ease of access and geographical location, LNGS are the ideal place to carry out complex experiments. The success of LNGS is closely linked to the ability to provide integrated services and scientific support of excellence in the fields of mechanics, electronics, the selection of radio-pure materials, analytical chemistry and scientific computing.
To keep LNGS in step with international competition, constant improvement is required. The LNGS FUTURE project aims at the modernization and strengthening of the laboratory's technical and safety services and at the creation of support for advanced cryogenics, a technique increasingly used by new generation experiments.
The ultimate goal is to host the most sensitive experiments designed to study relevant topics in astro-particle physics, nuclear astrophysics, and cosmology.
SNOLAB is Canada's deep underground laboratory, which has been fully operational since 2012. SNOLAB is operated 2 kilometers below ground in an active nickel mine, and the partnership with the local mine poses both opportunities and challenges. We will describe the operational capabilities, scientific program, and infrastructure challenges over the past decade and in the future.
Axions are considered the most favored solution for explaining both the strong-CP problem and the dark matter mystery. Many experimental searches that rely on the axion-photon conversion under strong magnetic fields utilize the haloscope technique that is sensitive in the microwave region. We, the Center for Axion and Precision Physics Research (CAPP) of the Institute for Basic Science (IBS), have been exploring axion physics in various frequency ranges. In particular, an experiment with a 12T superconducting solenoid, a high-cooling power dilution refrigerator, and quantum-noise-limited devices enable us to achieve unprecedented experimental sensitivities, probing the DFSZ axion model above 1 GHz. We are also developing state-of-the-art technologies in a variety of areas to enhance performance over a wider frequency range. In this presentation, the current status of axion search experiments and R&D activities at IBS-CAPP will be introduced, and future prospects will be discussed.
The International Axion Observatory (IAXO) is a new generation axion helioscope aiming at a sensitivity to the axion-photon coupling of gaγ down to 10-12 GeV-1, i.e. 1-1.5 orders of magnitude beyond CAST, the most sensitive axion helioscope to date. The main elements of IAXO are a large superconducting toroidal magnet with eight bores, x-ray focusing optics and low background detectors. An intermediate helioscope on the way to IAXO, called BabyIAXO, with the aim of testing the new technology for the full scale experiment, is being designed and will be located at DESY. The design of all components and assembly procedures is quite advanced. Due to the socio-political problems worldwide a delay has been accumulated for the fabrication of the magnet. We will discuss the strategy to perform important tests in the final BabyIAXO location at DESY on different instrumentation and mechanics in preparation to BabyIAXO while waiting for the magnet to be in place.
Once completed, BabyIAXO will be able to test gaγ down to 2×10-11 GeV-1. In addition, already with babyIAXO it will be possible to search for evidence of axion-electron and axion-nucleon coupling in the Sun. Moreover, installing cavities or antennas in the magnet bores will turn BabyIAXO into an axion haloscope, sensitive to dark matter axions in different mass ranges. We will discuss the physics reach of BabyIAXO and present the enhanced sensitivity for axion discovery which will be possible to obtain with the full scale IAXO.
One of the most well-motivated candidates to be the dark matter is the axion, a particle that is predicted by the solution to another long-standing mystery in physics, the strong CP problem. This talk discusses direct searches for low-mass axion dark matter via its photon interactions. The prototype experiment ABRACADABRA-10 cm developed an innovative lumped-element detection method to search in this mass range and set world-leading limits on axions. It also laid the stage for the DMRadio program, a series of larger detectors that will be capable of finding QCD axions and axion-like particles over a large range of masses below 1 μeV. Here I review the DMRadio experiments, including ongoing progress and plans for the future.
The DMRadio program consists of a series of lumped element detectors searching for low mass, sub-μeV axion dark matter. The three DMRadio detectors will each be comprised of a superconducting magnet and pickup structure coupled to a high-Q tunable LC resonator. In this talk, I will outline the calibration plan these experiments will employ to determine their end-to-end sensitivity to axion dark matter. A variety of methods will be used, including a mimetic axion signal injected into the detector, resonator noise measurements, multichannel SQUID chain calibration, and sideband injection. These results will allow us to characterize lumped element detectors and convert raw detector data into limits on axion to two photon coupling.
The experiments in the DMRadio program are designed to search for low mass sub-μeV axion dark matter using the coupling of axions to photons. Specifically, DMRadio-m$^3$ is designed to have sensitivity to KSVZ and DFSZ QCD axions in the 40-830 neV (10-200 MHz) range. A dc solenoidal magnetic field sources an axion current inside a coaxial pickup structure whose resonance frequency is tuned using lumped tuning elements. In this talk, we present the sensitivity of DMRadio-m$^3$. The primary science goal of sensitivity to DFSZ axions across 30–200 MHz can be achieved with a 3$\sigma$ live scan time of 3.7 years. This is informed by extensive finite element electromagnetic modeling of the pickup structure of the system, which will also be presented.
Quantum Sensors for the Hidden Sector is a UK collaboration developing ultra-low-noise readout and resonant detector technology, aiming initially to search for halo axions in the mass range 25-40 micro-eV. We describe our design, based on a 20cm bore 8T magnet in a dry dilution refrigerator supplied by Oxford Instruments having a target physical temperature of 10mK. We discuss progress towards construction and operation, and collaborative work with the US ADMX collaboration on cavity design and fabrication, data analysis, and novel resonator configurations.
Recent work indicates that nonequilibrium quasiparticles can contribute to decoherence effects in superconducting qubits. Ionizing radiation, for example, has been shown to create space- and time-correlated errors in qubit arrays. For quantum computing, such correlated errors can create problems for standard error correcting codes. For quantum sensing, these same phenomena represent a source of background error. We present preliminary work with an array of weakly charge-sensitive superconducting qubits, in a low-background test stand 100 meters (225 m.w.e.) underground at Fermilab's MINOS experimental area. Combined with measurements at the Earth's surface, this suite of underground, low-background measurements will help to quantify the effects of quasiparticle burst events in qubit arrays. Furthermore, these studies will inform the design of the new Quantum Science Center (QSC) underground quantum facility at Fermilab, QUIET.
Noble gas detectors are a leading technology in low energy rare-event
search experiments. The dominant source of background in these experiments is induced by radioactive decays of radon (and its daughter nuclides), which emanates from detector materials and distributes in the detection volume.
Thorough material selection and surface cleaning are important
measures against radon emanation. They may be combined with continuous
active radon removal techniques (by adsorption or distillation) to
reach a background level of less than 1 µBq/kg as recently demonstrated
by the XENONnT experiment. But to meet the even more demanding purity
goals of next-generation experiments, novel radon mitigation
techniques are required to complement the existing ones.
We have explored the applicability of surface coatings as barriers
against radon emanation. The approach requires a diffusion-tight, thin
and mechanically stable coating layer, which itself does not contain
radon sources. In the talk I will discuss different coating methods
that have been studied and focus on recent results of the most
promising technique: Electro-deposition of thin copper films. Using a
custom-made stainless steel $^{222}$Rn source produced at the ISOLDE
facility at CERN, a $^{222}$Rn suppression of more than a factor 1000 has
been achieved. Possible applications and future challenges of this
technique will be discussed.
The LUX-ZEPLIN (LZ) experiment, a dual-phase xenon time projection chamber operating from the Sanford Underground Research Facility in Lead, South Dakota, USA, aims to detect Weakly Interacting Massive Particles (WIMP) dark matter candidate particles. It comprises a 10-tonne target mass (7-tonne active) viewed by vacuum ultraviolet photomultiplier tubes in both the liquid xenon's central and self-shielding regions, enclosed within an active gadolinium-loaded liquid scintillator veto and all submerged in an ultra-pure water tank veto system. This talk will provide an overview of the LZ detector, present results from LZ's first science run (exposure of 60 d × 5.5 t.) and give an update on the current efforts being undertaken by the LZ Collaboration.
The main goal of the XENONnT detector is the direct detection of Weakly Interacting Massive Particles (WIMPs), aiming to improve the sensitivity by one order of magnitude than XENON1T. The first science run has been completed in 2021 with a total exposure of 1.1 tonne*year. An extremely low electronic recoil background of 15.8 events/(t y keV) has been achieved thanks to the reduction of Kr-85 and Rn-222. More data is being accumulated now. In this talk, I will give an overview of the XENONnT experiment as well as its first WIMP search results.
Located at China Jinping Underground Laboratory, PandaX experiment uses xenon as target to detect rare physics signals like dark matter. The new generation detector with 4-ton xenon target volume, PandaX-4T, has pushed the constraints on WIMP-nucleon scattering cross-section to a new level with its commissioning run data. In this talk, I will give an overview of PandaX-4T latest results on dark matter, exploring the physics capability of xenon detector.
PandaX-4T is the first operational multi-tonne experiment for dark matter direct search in China, which released its first commissioning data in 2021 and gained world-leading sensitivity to WIMP at the time. With further lowered energy thresholds and improved analysis techniques, searches for solar neutrino and light dark matter have been carried out. In this talk, I’ll talk about the recent progress in the search of solar B8 neutrino and light dark matter using PandaX-4T data.
The LUX-ZEPLIN (LZ) dark matter search experiment, a dual-phase xenon time projection chamber operating at the Sanford Underground Research Facility in Lead, South Dakota, USA, has the world's leading sensitivity to searches for Weakly Interacting Massive Particles (WIMPs). It is comprised of a 7-tonne target mass and outfitted with photomultiplier tubes in both the central and the self-shielding regions of the liquid xenon, which is enclosed within an active gadolinium-loaded liquid scintillator veto and all submerged in an ultra-pure water tank veto system. LZ has completed its first science run, collecting data from an exposure of 60 live-days. This talk will provide an overview of LZ’s search and sensitivity goals to a model-agnostic Effective Field Theory (EFT) framework that describes several possible dark matter interactions with nucleons. In this talk, we highlight the key backgrounds, data analysis techniques, and signal models relevant to this study.
The CRESST-III (Cryogenic Rare Event Search with Superconducting Thermometers) experiments main goal is the direct detection of dark matter particles via their scattering off target nuclei in cryogenic detectors. The detectors are equipped with transition edge sensors (TES), operated at around 15 mK. These sensors reach sensitivities down to very low energy depositions ( ≤ 100 eV), allowing for the search of dark matter particles with sub-GeV masses. This contribution presents the analysis and results of an Al$_{2}$O$_{3}$ detector with a mass of 0.6 g. This detector could be calibrated via the detection of single luminescence photons in the eV-range, which were observed in CRESST for the first time. The low threshold of this detector (≤ 10 eV) allows for the calculation of a dark matter exclusion limit of masses below 100 MeV /c$^{2}$.
We present a detailed density functional theory (DFT) study of the electronic structure of atomic and liquid xenon to quantify the event rates in Xe-based detectors for dark matter (DM) – electron scattering. Our main goal is to determine whether explicit modelling of the inter-atomic interactions of the liquid phase changes the predicted rates compared to state-of-the-art models based on isolated Xe atoms.
We start by identifying DFT parameters that correctly reproduce the experimental valence-electron binding energies for an isolated Xe atom. Next, we use solid crystalline xenon as a benchmark for verifying our calculations of the inter-atomic van der Waals interactions and identify a DFT setup that reproduces the experimental lattice parameter and band structure. We then model liquid xenon by creating a spatial distribution of atoms via a classical Monte-Carlo simulation with a Lennard-Jones potential, which we match with the experimental radial distribution function. We construct computationally tractable DFT input structures by sampling different regions of the distribution. We find that averaging calculations over multiple such structures gives good convergence and reproduces well the experimental refractive index of liquid xenon.
Finally, we compare the calculated form factors and rates for our DFT atom with previous semi-analytical results obtained using atomic Roothaan-Hartree-Fock wavefunctions, as well as with our DFT results for the liquid state.
The Dark Matter Data Center (DMDC) is an ORIGINS Excellence Cluster initiative, supported by the Max Planck Computation and Data Facility. It aims at bringing together the large amount of recorded data and theories pertaining to Dark Matter (DM) research in a unified platform, making it easily accessible for the community. The DMDC offers a repository where data, methods and code are clearly presented in a unified interface for comparison, reproduction, combination and analysis. It is a forum where Experimental Collaborations can directly publish their data and Phenomenologists the implementation of their models, in accordance to Open Science principles. Alongside the repositories, it also offers easy online visualization of the hosted data. An online simulation of signal predictions for experiments using model data supplied by the users is also in the offing, all in a friendly web-based GUI. The DMDC also hosts guidance tools from the Collaborations illustrating the usage and analysis of their data through Binders that run online and support all popular programming platforms. It hosts a continuously growing compendium of ready-to-use, copy-pastable code examples for inference and simulations. It can also provide support and computational power for comparison of model and experimental observations as well as the combination of these results using modern and robust statistical tools through similar Binders.
GAPS is a balloon-borne particle-tracker searching for signals of dark matter from low-energy (kinetic energy $\leq 0.25$ GeV/n) cosmic antideuterons. In standard astrophysics, antideuteron production is kinematically suppressed at low energies; consequently, low-energy cosmic antideuterons are a nearly background-free signal of dark matter annihilation or decay. GAPS will make a precision measurement of the antiproton spectrum in a previously-unexplored low-energy range, allowing it to place new constraints on primordial black holes. Finally, GAPS will offer the leading sensitivity to low-energy antihelium-3, a signal of new physics. GAPS will achieve these goals utilizing a novel detection technique based on the formation, deexcitation, and annihilation of exotic atoms. The GAPS instrument has two detecting subsystems: a time-of-flight and a particle tracker. The Time-of-flight is composed of 160 plastic scintilator paddles and their custom read-out electronics. The tracker consists of $\sim$ 1000 lithium-drifted silicon detectors which are read out with custom ASICs. The experiment is being integrated and undergoing calibration and testing, in advance of its first Antarctic long-duration balloon flight in the austral summer of 2024. This presentation will review the science motivation for antideuteron searches for dark matter, describe the GAPS experiment, and report the status of the GAPS instrument along with results from our ground testing.
The High Energy Particle Detector 01 (HEPD-01) is one of the payloads on board of CSES-01, the China Seismo-Electromagnetic Satellite dedicated to monitoring perturbations of electromagnetic fields, plasma and charged particle fluxes induced by natural sources and artificial emitters in the near-Earth space.
It is designed to measure electrons, protons and light nuclei (up to a few hundreds of MeV) with a high energy resolution and a wide angular acceptance. It has been launched in February 2018 on a Low-Earth Orbit and an altitude of about 507 km.
In this work, the analysis on galactic helium nuclei spectra with energy >60 MeV in the period August 2018 - January 2020 will be presented. The clear particle separation of different nuclei inside the detector allows to select a pure sample of helium. This analysis technique is shown for the first time, together with the calculated flux on a semi-annual basis of HEPD-01 data and the comparison with the theoretical spectra.
Below 5 GeV, the ratio proton/helium strongly depends on the solar modulation. As the mass-to-charge ratio for these two species is different, the determination of this quantity is fundamental for the cosmic-ray propagation model in the Galaxy. The HEPD-01 galactic proton and helium spectra are compared and the result will be shown, allowing to explore an energy range where there are no recent direct measurements.
Deuterons are the most abundant secondary nuclei in cosmic rays and precise measurement of their properties will allow to test and constrain various cosmic ray propagation models.
The precision measurement of deuteron flux with kinetic energy per nucleon from 0.2 GeV/n to 9 GeV/n based on 15 million deuterons collected by Alpha Magnetic Spectrometer during first 10 years of operation on International Space Station is presented. The deuteron-to-proton and deuteron-to-4helium flux ratios are also shown, together with their time evolution over a almost complete solar cycle.
Lithium and Beryllium nuclei in cosmic rays are expected to be secondaries produced by the fragmentation of primary cosmic rays during their propagation in the Galaxy. Therefore, their fluxes contain essential information on cosmic ray propagation and sources. Secondary-to-primary flux ratios provide measurements of the material traversed by cosmic rays in their journey through the Galaxy. The Li and Be isotopic compositions provide crucial complementary information. In particular, the $^{10}$Be/$^9$Be ratio measures the cosmic ray propagation volume in the Galaxy, and the $^6$Li/$^7$Li ratio tests the existence of primordial lithium. Current measurements of the $^6$Li/$^7$Li and $^{10}$Be/$^9$Be ratios are limited to energies below 1 GeV/n and 2 GeV/n, respectively, and are affected by large uncertainties. Individual fluxes of $^6$Li and $^7$Li, and of $^7$Be, $^9$Be and $^{10}$Be, have only been measured below 0.3 GeV/n and 0.4 GeV/n, respectively. In this contribution, we present the measurement of the $^6$Li and $^7$Li fluxes and their ratio, and of the $^7$Be, $^9$Be, $^{10}$Be fluxes and their ratios, in the uncharted energy region ranging from 0.4 GeV/n to 12 GeV/n based on data collected by AMS during its first 10 years of operation on the International Space Station.
Introduction: Nearby supernova explosions may cause isotope anomalies via several processes, one of which is cosmic-ray spallation in the earth's atmosphere. We estimate the direct production rates of cosmogenic nuclides, showing the dependence on the supernova distance. This is a not a new idea: in fact we started our studies a few years ago, however due to some inconsistencies it took longer to come with some reliable results.
Calculations: We have performed a set of calculations to determine the expected $^{10}$Be contribution from a SN explosion. We have assumed a power law for the differential GCR flux (with exponent -2.48) and we have taken only nitrogen, oxygen and argon for the composition of atmosphere.
For reactions induced by cosmic radiation, production rates were calculated with the GEANT 4 [1] code system. Besides direct production of $^{10}$Be also the secondary neutron fluxes were calculated. Production of neutrons by photons should be calculated with respect of high flux of impacting photons. Having calculated the neutron fluxes, the production rates of $^{10}$Be were calculated following the approach described in [2].
Conclusions: Calculated production rates were compared with experimental data from ice samples. Conclusions about possibility to find in data nuclides produced by SN explosions were made.
References:
[1] S. Agostinelli et al., NIM A, vol. 506, no. 3 (2003) 250-303.
[2] Masarik J and J. Beer,(1999) JGR, A104. 12,099-12,111.
NUSES is a new space mission project aimed at studying cosmic and gamma rays, high-energy astrophysical neutrinos, the Sun-Earth environment, space weather, and magnetosphere-ionosphere-lithosphere coupling (MILC). Additionally, the NUSES mission will serve as a technological pathfinder for the development and testing of innovative technologies and observational strategies for future missions. The satellite will host two payloads named TERZINA and ZIRÈ. ZIRÈ will perform measurements of electrons, protons, and light nuclei from a few up to hundreds of MeV, while also testing new tools for the detection of cosmic MeV photons and monitoring of MILC signals. The Terzina telescope aims to detect ultra-high-energy cosmic rays (UHECRs) through the Cherenkov light emission from extensive air showers that they create in the Earth's atmosphere. The telescope will also monitor the light emissions from the Earth limb in the near-UV and visible ranges at the nanosecond timescale, thus testing the observational concept of detecting Earth skimming astrophysical high-energy neutrinos. Terzina will be able to study the potential for future physics missions (e.g. POEMMA) devoted to UHECR detection and UHE neutrino astronomy. In this talk, the status of the NUSES project design will be discussed along with the scientific and technological objectives of the mission.
The accretion disk that forms following a neutron star merger ejects a significant amount of matter that contributes to the appearance of the kilonova transient and the chemical evolution of the Universe. Irradiation of this ejecta by electron neutrinos and antineutrinos changes the composition of this outflow, but neutrinos are also known to change flavor on timescales of nanoseconds (so-called "fast-flavor oscillations"), the consequences of which are not well understood. Based on the neutrino radiation field drawn from a three dimensional neutron star merger simulation, we perform local (centimeter-scale) three-dimensional two-flavor simulations of the fast flavor instability using an extension of the truncated moment formalism to neutrino quantum kinetics. We discuss the validity and advantages of this method by comparing the results against two- and three-flavor particle-in-cell simulations, as we get generally good agreement in the instability growth rate and the final flavor abundances.
Collapsar jets may be copious factories of high energy neutrinos, whose production takes place through photo-hadronic and hadronic interactions. Since neutrinos point back to the source that produced them, they have the potential to unravel puzzling features displayed by astrophysical objects. We post-process the outputs of state-of-the-art general relativistic magneto-hydrodynamic simulations of collapsar jets and investigate possible sites of particle acceleration and neutrino production in the deepest outflow regions. If the jet is magnetized, subphotospheric neutrinos with energies up to $E_\nu \leq \mathcal{O}(10^5)$ GeV can be produced through collisionless sub-shocks and magnetic reconnection. More than one neutrino event could be observed in Hyper-Kamiokande and IceCube DeepCore for nearby jets. Such a signal is only expected from magnetized outflows. Hence, follow-up searches in the direction of transients harboring relativistic jets with existing and upcoming neutrino telescopes will be crucial to unravel the nature of collapsar jets.
In this talk we discuss the impact of cosmological measurements on future searches for neutrinoless double-beta decay (0nbb). The fundamental importance of 0nbb for particle physics -- in particular for neutrino physics -- is well known and many efforts are underway to push the experimental sensitivity to values of the half-life of the process above 10^27 years. Current cosmological results already allow us to place stringent constraints on Majorana's effective mass, i.e. the electron-type mass of ordinary neutrinos; tighter limits and more precise information are expected in the near future. In this context, we quantify the probability of discovering 0nbb for next-generation experiments by updating and extending a broad line of investigation we have conducted over the years*. We minimize assumptions on unknown parameters, such as Majorana phases, and present a new graphical representation of the results, of relevance to the 0nbb community.
* PRD 90, 033005 (2014) / JCAP 12 (2015) 023 / PRD 100, 073003 (2019) / PRD 103, 033008 (2021) / arXiv:2202.01787 (accepted by RMP)
We consider the minimal see-saw extension of the Standard Model with two right-handed singlet fermions with mass at the GeV scale, augmented by an effective dipole operator between the sterile states. We firstly review current bounds on this effective interaction from fixed-target and collider experiments as well as from astrophysical and cosmological observations. We then highlight the prospects for testing the radiative decay of the heaviest neutrino induced by the dipole at facilities targeting long-lived particles such as FASER and SHiP.
Massive liquid argon TPCs developed for DUNE have significant potential in the physics of MeV neutrinos and offer unprecedented opportunities for the observation of solar neutrinos. The SoLAr collaboration has proposed an innovative readout system to enhance the physics reach of the DUNE Module of Opportunity, perform high-precision measurements of 8B neutrinos, and provide the first observation of solar neutrinos from the Helium-proton fusion (HEP neutrinos). In this talk, we summarize the status of the project and the results obtained in 2022-23. The novel light-charge readout system by SoLAr was tested in a dedicated prototype and we present the first combined light-charge measurements with cosmic rays obtained at the University of Bern. Thanks to the prototyping and simulation results, we update the physics reach of SoLAr with an emphasis on background mitigation. Finally, we present the perspectives for the implementation of SoLAr in DUNE and the validation of this novel technology at the Boulby underground laboratories.
Borexino was a solar neutrino detector based on 280 tons of ultrapure liquid scintillator, located at the Laboratori Nazionali del Gran Sasso, Italy. Over fourteen years of data taking, Borexino completed the spectroscopy of solar neutrinos emitted from the pp chain reactions and measured the flux from the Carbon-Nitrogen-Oxygen (CNO) cycle. These spectroscopy analysis relied on a multivariate fit to disentangle the neutrino signal from the backgrounds, based on the events energy and radial position. For the CNO signal search, an additional constraint to the annoying 210Bi background rate, independent of the spectral fit, was necessary to gain enough sensitivity. Recently, Borexino has demonstrated the use of the directional Cherenkov information for a sub-MeV solar neutrinos measurement, in a liquid scintillator detector. This "Correlation and Integrated Directionality" (CID) technique correlates the individual photon hits of events to the position of the Sun.
This talk covers the Borexino search for CNO signal by exploiting the CID technique.
Exploiting this method only we achieved, for the first time, a CNO flux measurement without imposing any independent constraint to the 210Bi rate. In addition, we have combined an improved two-dimensional multivariate analysis with the information on pep+CNO number of events obtained from the CID analysis, leading to the most precise CNO measurement ever obtained by Borexino.
CPT invariance is a key pillar in our description of nature. Neutrinos, as elementary particles, provide a unique opportunity to test this fundamental symmetry. In this talk, I will discuss how next-generation solar neutrino and medium-baseline reactor experiments will allow constraining (or proving) CPT violation with unprecedented confidence. Moreover, I will discuss how non-standard neutrino interactions could mimic CPT-violating signatures and the prospects to disentangling both scenarios.
The Jiangmen Underground Neutrino Observatory (JUNO), currently under construction in South China, will be the largest liquid scintillator (LS) experiment. While its primary goals are determining the neutrino mass ordering (NMO) and precision measurements of the oscillation parameters, it is a multi-purpose detector capable of detecting neutrinos from sources like the Sun, supernovae, the Earth, and the atmosphere other than reactors. With excellent detector performance in energy resolution (3% at 1 MeV) and low background level (10$^{-17}$ g/g U238/Th232) in such a large LS detector (20 kton), a rich program of non-oscillation related physics expanding from several tens of keV to tens of GeV can be explored. In this talk, the physics potential with various astrophysical and natural terrestrial neutrino sources, as well as rare event searches such as proton decay, will be presented.
The Jiangmen Underground Neutrino Observatory, is a multipurpose neutrino experiment located at 53 km from the Yangjiang and Taishan nuclear power plants in south-east China. Its main purpose is determining the neutrino mass ordering using precision spectral measurement of the reactor neutrino signal. The detector is composed of a 20 kiloton spherical liquid scintillator (LS) volume seen by 17612 20" photomultiplier tubes (PMT) and 25600 3" PMTs. The LS volume is enclosed in a water Cerenkov veto filled with 34 kton of ultrapure water seen by 2400 20" PMTs. A muon tracker composed of 3 layers of plastic scintillator strips surmounts the LS volume. The neutrino detection is done through inverse beta decay (IBD) resulting in a two-fold signal given by the positron and the neutron capture on H after ∼200μs. Various processes can mimic IBD, hence contributing to the background in the detector: natural radioactivity, cosmogenic isotopes, fast neutrons and (α,n) reactions are the major backgrounds of the reactor neutrino signal. A set of cuts including fiducial volume, energy, PSD, time-position correlation of the prompt and delayed signal helps to mitigate accidentals and (α,n) backgrounds. To reject the cosmogenics induced by muons with a rate of ∼4Hz, muon veto cuts are necessary: an optimized volume around the muon track or cosmic-induced neutron is vetoed. In this talk, we'll present the backgrounds to the neutrino signal and the veto strategies to mitigate these backgrounds.
LiquidO is a class of particle detection technology utilising opaque media for its light detection. The technology exploits the stochastic confinement of light in such media, which allows to identify the types of individual charged and neutral particles through the topology of their energy depositions. This technology extends the traditional scintillation detector by a vertex resolution of roughly one centimetre. At energies above a few MeV, the detector technology shows tracking capabilities and therefore offers a wide range of applications in particle physics.
In this contribution, we will present this novel technology and show results on the stochastic light confinement using the wax-based scintillator NoWaSH. We will further address current and future projects which are planning to use the opaque technology for fundamental neutrino physics, reactor monitoring or medical physics, such as SuperChooz, AM-OTech, and LPET.
This talk will cover recent R&D on Water-based Liquid Scintillator, including work on slowing down the timing to enhance scintillator/Cherenkov separation, and also preliminary work on isotope loading. In addition, I will present the status of the 30-ton WbLS prototype now under construction at Brookhaven and plans for future R&D.
FASER$\nu$ at the LHC is designed to directly detect collider neutrinos of all three flavors and provide new measurements of their cross-sections at energies higher than those seen from any previous artificial sources. We observed the first neutrino interaction candidates at the LHC in the 2018 pilot run data and then reported the firm observation of neutrino interactions in the 2022 data, opening a new avenue for studying neutrinos from high-energy colliders. In 2022-2025, during LHC Run 3, we expect to collect $\sim$2,000 $\nu_e$, $\sim$6,000 $\nu_{\mu}$, and $\sim$40 $\nu_{\tau}$ charged-current interactions in FASER$\nu$, along with neutral-current interactions. Here we present the latest results from FASER$\nu$.
The European Spallation Source neutrino Super Beam (ESSνSB) is a design study for a long-baseline neutrino experiment to measure the CP violation in the leptonic sector at the second neutrino oscillation maximum using a neutrino beam driven by the uniquely powerful ESS linear accelerator. The reduced impact of systematic errors on sensitivity at the second maximum allows for a very precise measurement of the CP violating parameter. The ESSνSB CDR showed that after 10 years of data taking, more than 70% of the possible CP-violating phase, $δ_{CP}$, range will be covered with 5σ C.L. to reject the no-CP-violation hypothesis. The expected value of $δ_{CP}$ precision is smaller than 8° for all $δ_{CP}$ values, making it the most precise proposed experiment in the field by a large margin. The recently started extension project, the ESSνSB+, aims in designing two new facilities, a Low Energy nuSTORM (LEnuSTORM) and a Low Energy Monitored Neutrino Beam (LEMNB) to use them to precisely measure the neutrino-nucleus cross-section (the dominant term of the systematic uncertainty) in the energy range of 0.2 – 0.6 GeV. With the successful end of the previous design-study programme of the experiment, an overall status of the project will be presented together with the ESSvSB+ additions.
The Short-Baseline Near Detector (SBND) will be one of three Liquid Argon Time Projection Chamber (LArTPC) neutrino detectors positioned along the axis of the Booster Neutrino Beam (BNB) at Fermilab, as part of the Short-Baseline Neutrino (SBN) Program. The detector is anticipated to begin operation later this year. SBND is characterized by superb imaging capabilities and will record over a million neutrino interactions per year. Thanks to its unique combination of measurement resolution and statistics, SBND will carry out a rich program of neutrino interaction measurements and novel searches for physics beyond the Standard Model (BSM). It will enable the potential of the overall SBN sterile neutrino program by performing a precise characterization of the unoscillated event rate, and constraining BNB flux and neutrino-argon cross-section systematic uncertainties. In this talk, the physics reach, current status, and future prospects of SBND are discussed.
Neutrinos are Standard Model particles that lead us to many open questions. Very abundant but yet challenging to detect, they are a key towards physics beyond the Standard Model and they play a role in major questions about our Universe. In particular, the Dirac phase of CP symmetry violation ( $\delta_{CP}$) that parameterizes the asymmetry in flavor oscillation probabilities between neutrino and anti-neutrinos is one of the most studied parameters. If $\sin(\delta_{CP})$ is non-zero, this would mean that neutrinos, and the leptonic sector in general, may participate in the unexplained matter/anti-matter asymmetry of the Universe via yet-to-be-discovered leptogenesis mechanisms.
The neutrino oscillation long baseline program in Japan is currently leading the sensitivity to CP violation in neutrino oscillations. More specifically, the Tokai to Kamioka (T2K) experiment measures muon neutrino disappearance and electron neutrino appearance in a 600 MeV accelerator beam of (anti-) neutrinos with a baseline of 295 km. Its sensitivity is based on a complex set of near detectors, both on- and off-axis, as well as an off-axis water Cherenkov far detector.
We will present here the analysis principle, with a focus on the far detector fit, and the latest accelerator neutrino oscillation results.
The Deep Underground Neutrino Experiment (DUNE) is a next generation, long-baseline neutrino oscillation experiment which will utilize high-intensity $\nu_{\mu}$ and $\bar{\nu}_{\mu}$ with peak neutrino energies of ~2.5 GeV produced at Fermilab, over a 1285 km baseline, to carry out a detailed study of neutrino mixing. The unoscillated neutrino flux will be sampled with a near detector complex at Fermilab, and oscillated at the DUNE far detector at the Sanford Underground Research Facility, which will ultimately consist of four modules each containing a total liquid argon mass of 17 kt.
Here, the long-baseline neutrino oscillation sensitivity of DUNE is determined, using a full simulation, reconstruction, and event selection of the far detector and a full simulation and parameterized analysis of the near detector. Detailed uncertainties due to the flux prediction, neutrino interaction model, and detector effects are included. DUNE's ultimate precision on CP-violation and the value of the CP-phase are discussed, along with DUNE's ability to resolve the mass ordering, the $\theta_23$ octant, and DUNE's expected precision on other oscillation parameters of interest.
The Jiangmen Underground Neutrino Observatory (JUNO) is a multi-purpose neutrino observatory under construction in China. It will host a 20 kt liquid scintillator detector underground with an overburden of 700 m to study the neutrinos from different neutrino sources. With an unprecedented energy resolution of 3% at 1 MeV, JUNO is designed mainly to detect the anti-neutrinos from the nuclear power plants located $\approx$ 53 km from the detector. One of the main physics goals of the experiment is to determine the neutrino mass ordering (MO) and to precisely measure the neutrino oscillation parameters $\Delta m^2_{21}$, $\sin^2\theta_{12}$, and $\Delta m^2_{31}$ using the reactor anti-neutrino flux. It is estimated that using six years of data, JUNO will determine the neutrino MO with a significance of $3\sigma$ and also determine the parameter $\Delta m^2_{31}$ with a precision of $\approx 0.2\%$. Meanwhile, the parameters $\Delta m^2_{21}$ and $\sin^2\theta_{12}$ will be determined with a precision of $\approx 0.3\%$ and $\approx 0.5\%$ respectively. The results from JUNO are expected to improve upon the existing knowledge of precision on these three parameters by almost one order of magnitude. Additionally, JUNO can also measure neutrino oscillations using solar and atmospheric neutrinos. This talk will mainly report on the physics of neutrino oscillations with the reactor neutrinos at JUNO, and discuss the analysis strategy used in estimating these parameter sensitivities.
A new Quantum Field Theory (QFT) formalism for neutrino oscillations in a vacuum is proposed. The neutrino emission and detection are identified with the charged-current vertices of a single second-order Feynman diagram for the underlying process, enclosing neutrino propagation between these two points. The critical point of this approach is the definition of the space-time setup typical for neutrino oscillation experiments, implying macroscopically large but finite volumes of the source and detector separated by a sufficiently large distance, L. The L-dependent master formula for the charged lepton production rate is derived, which provides the QFT basis for analyzing neutrino oscillations. It is demonstrated that our QFT formula coincides with the conventional one under some assumptions for some particular choice of the underlying process. Further, techniques are developed for constructing amplitudes of neutrino-related processes in terms of the neutrino mass matrix, with no reference to the neutrino mixing matrix. The proposed approach extensively uses Frobenius covariants within the framework of Sylvester’s theorem on matrix functions. It is maintained that fitting experimental data in terms of the neutrino mass matrix can provide better statistical accuracy in determining the neutrino mass matrix compared to methods using the neutrino mixing matrix at intermediate stages.
The underground ultra-low background laboratory STELLA (SubTerranean Low Level Assay) in the Laboratori Nazionali del Gran Sasso of the National Institute of Nuclear Physics (LNGS-INFN) is principally dedicated to material screening measurements for fundamental physics experiments installed in the underground laboratories. It is mainly using gamma-ray spectrometry, but also alpha and beta spectrometry on small selected samples. The high level of performance of the ultra-low background detector systems allow for analysing extremely low concentrations of natural and man-made radioactivity in a wide range of materials down to a level of few $\mu$Bq $kg^{–1}$.
Thanks to the extremely low background levels of the gamma-ray detection systems (ultra low background high purity germanium detectors) also basic physics results on rare radioactive decays are obtained that in some cases could also give rise in the future to new detector technologies for experiments searching for these rare radioactive decays.
The installations and experimental set-ups using ultra-low background techniques will be described shortly, and examples of significant measurements for both applications, material screening and basic physics, will be presented. Finally, the planned future upgrade of the STELLA laboratory and its possible impact will be discussed.
Experiments studying rare event searches, such as dark matter interactions and neutrinoless double beta decay, require ultra-low levels of radioactive backgrounds in their own construction materials, shielding and in the surrounding environment. As the next generation of experiments are becoming even more sensitive, material selection has become one of the most crucial components of the design process for these experiments to reduce these backgrounds to be as low as reasonably achievable. The SNOLAB low background counting program has developed several different methods to directly measure these experimental backgrounds. This presentation will review the low background measurement facilities at SNOLAB currently used to measure these backgrounds, describe the data analysis techniques used and present the capabilities of these detectors. Furthermore, plans and options to expand these facilities will be discussed, and a program to measure environmental backgrounds at the SNOLAB underground laboratory will be outlined.
The Nuova Officina Assergi (NOA) is a functional Research and Technological Unit operational at LNGS since autumn 2022. Conceived and built within the framework of the DarkSide-20k experiment, it is the most advanced infrastructure flagship of the INFN, for the production and integration of silicon devices operating at cryogenic temperatures. It consists of a ISO6 clean room of 420 m2 designed to work with a reduced radon concentration and is equipped with cutting-edge technology machines: a cryogenic Silicon device probe, a semi-automatic dicing system, a high-speed dual bond head flip-chip bonder and an ultrasonic wedge-wedge and ball-wedge wire bonder. The next two years the facility will host the DarkSide-20k activities for the packaging and assembly of large area cryogenic photosensors,customized by FBK and transferred to LFoundry for the massive production of more than 10000 optical modules. In perspective NOA, could offer a valid alternative to industrial processes, becoming an opportunity for all the collaborations and research centers, interested in the development of emerging technologies of interconnections for the integration of customized SiPMs. Possible field of interest could be backside-illuminated (BSI) devices and Trough Silicon Vias (TSV) or hybridization and module integration of hybrid and monolithic pixel detectors. In the following we will report in details the NOA facility as a possibility for assembling electronic devices for dark matter detectors.
The Online Scintillator Internal Radioactivity Investigation System is an 18-ton pre-detector of JUNO, currently under commissioning in south-west China. During the 6-month filling phase of the JUNO main detector, it will be responsible for the monitoring of the radiopurity of the liquid scintillator filled into the JUNO central detector. Fast 214/212Bi/214/212Po coincidences serve as a main measurement channel for OSIRIS’ high sensitivity to 238U/232Th contaminations in the liquid scintillator. In addition, contamination measurements of 85Kr and 14C are also foreseen. OSIRIS is located 700m underground in the JUNO laboratory near the central detector. Its cylindrical central vessel is surrounded by 64 JUNO 20-inch PMTs and embedded into a water Cherenkov muon veto. Calibration of the detector will be done by an automated calibration unit featuring radioactive sources and a fast pulsed LED, as well as by a pico-second laser calibration system responsible for time- and charge calibration. After OSIRIS’ main purpose of monitoring the liquid scintillator has been fulfilled, a consecutive physics phase addressing solar neutrinos and 0νββ decay is foreseen.
PandaX is a set of xenon-based time projection chambers designed for detecting rare events such as dark matter and neutrino interactions. Background control is a crucial aspect of these searches. For material screening, we utilized HPGe, ICP-MS, and NAA techniques, as well as custom-built krypton, radon-emanation, and alpha measurement systems. In this report, we present our radioassay program and the measured background rates at the PandaX-4T detector. We also discuss ongoing efforts to further reduce background in the next-generation PandaX liquid xenon detector.
The DarkSide-20k experiment searches for dark matter by looking for interactions of WIMPs in a 50 tonnes target of liquid argon using double-phase time projection chamber technology. The key component of the experiment is low radioactivity argon depleted in the isotope $^{39}$Ar.
The supply chain begins with the Urania plant in Colorado, which can produce argon at a purity of 99.99% from a CO$_2$ stream sourced from a deep well that reaches the Earth’s mantle, at a rate of about 250 kg/day. The plant, which includes four distillation columns and a pressure swing absorption stage, has already been fabricated while the site is being prepared for installation. After this initial purification stage, the argon will be transported to Sardinia, Italy, where the Aria plant, based on a 350 m cryogenic distillation column, will further suppress impurities by several orders of magnitude. The Aria plant has already been fully fabricated and is now in the installation phase. A lower version, about
26 m high, has been tested over the last three years with very positive results confirming the cryogenic distillation technology.
The importance of this supply chain and of associated techniques extends well beyond DarkSide-20k. Low-radioactivity argon is also of interest for the LEGEND-1000 experiment and for the ultimate dark-matter search experiment using argon ARGO and is attracting the attention of the DUNE collaboration for its Module of Opportunity.
Rigorous radioactive background constraints are necessary for rare-event search experiments to meet their sensitivity goals. Underground facilities provide ideal attenuation of cosmic radiation, shielding materials around the detectors are used to mitigate backgrounds from soil, and extensive radioassay campaigns are performed to source the most radiopure materials. To reduce the impact of particulate deposition on material surfaces, detectors are assembled and operated in cleanroom facilities. Even so, dust particulate fallout on rare-event detector materials remains a concerning source of radioactive backgrounds. Within the low-background community, much effort is being invested to investigate, inform, and mitigate dust backgrounds. In this work, an ICP-MS based methodology for the direct determination of fallout rates of radionuclides and stable isotopes of interest from dust particulate was employed to monitor key experimental areas at the SNOLAB facility. Hosted in an active mine at a depth of 2070m, the SNOLAB underground laboratory strives to maintain experimental areas at class-2000 cleanroom level. This work provides insights on dust background mitigation procedures in place at SNOLAB, and informs backgrounds from dust particulate fallout during underground laboratory activities.
The radiopurity.org database has proven to be a valuable resource for the low background physics community as a tool to track and share assay results. This talk will describe recent collaborative efforts between the Pacific Northwest National Laboratory and SNOLAB to modernize the database for the community. Improvements to the search utility and data upload methods will be discussed. Installations to support individual physics collaborations and assay facilities will be described, as well as ongoing plans to develop and support the database.
We consider the mass spectroscopy of dark matter in the dark hadron model. In this model [1], the dynamical chiral symmetry breaking in the $SU(3)$ hidden color gauge sector, there exist Nambu-Goldstone (NG) bosons which are massive, because the hidden sector fermions break explicitly chiral symmetry. Therefore, these bosons are dark matter candidates. We study $SU(3)$ hidden color interaction and $SU(3)$ hidden flavor symmetry which can be broken into $SU(2)$ $\times$ $U(1)$. We present the mass spectroscopy of dark matter by lattice QCD simulations with a truncated overlap fermion formalism based on domain wall fermions. Truncated overlap fermions satisfy lattice chiral symmetry instead of chiral symmetry in continuum field theory.
[1] Ametani Y, Aoki M, Goto H, and Kubo J 2015 Phys. Rev. D 91 115007.
LEGEND-1000 is a next-generation experiment to search for neutrinoless double-beta decay of the Ge-76 isotope. This ton-scale experiment uses enriched high-purity Ge detectors surrounded by a large active liquid Ar shield, deployed deep underground. Because of the low noise and low energy thresholds of these detectors, along with the low background design of LEGEND-1000, this experiment provides an excellent opportunity for searches for new physics beyond neutrinoless double-beta decay. These include searches for dark matter candidates, exotic nuclear decays, tests of fundamental symmetries, emissions of additional particles during two-neutrino double-beta decays, and more. This poster will focus on the strategies and expected sensitivities of the experiment for these searches for physics beyond the standard model.
This work is supported by the U.S. DOE and the NSF, the LANL, ORNL and LBNL LDRD programs; the European ERC and Horizon programs; the German DFG, BMBF, and MPG; the Italian INFN; the Polish NCN and MNiSW; the Czech MEYS; the Slovak SRDA; the Swiss SNF; the UK STFC; the Russian RFBR; the Canadian NSERC and CFI; the LNGS, SNOLAB, and SURF facilities.
The creation of anti-nuclei in the Galaxy has been has been discussed as a possible signal of exotic production mechanisms such as primordial black hole evaporation or dark matter decay/annihilation, in addition to the conventional production from cosmic-ray (CR) interactions. Tentative observations of CR antihelium by the AMS-02 collaboration have re-energized the quest to use antinuclei to search for physics beyond the standard model.
In this talk, we show state-of-art predictions of the antinuclei spectrum from both astrophysical and standard dark matter annihilation models obtained from combined fits to high-precision antiproton data as well as CR nuclei measurements (specially B, Be, Li). Astrophysical sources are capable of producing $\mathcal{O}(1)$ antideuteron event and $\mathcal{O}(0.1)$ antihelium events over 15~years of AMS-02 observations. Standard dark matter models could potentially produce $\mathcal{O}(1)$ antihelium event, while the production of a larger antihelium flux would require more novel dark matter model building. We also discuss that annihilation/decay of a QCD-like dark sector could potentially explain the AMS-02 preliminary observations of antihelium-3 and antihelium-4.
Secondary photons in SiPMs are responsible for at least three processes: (i) internal cross-talk (ii) external cross-talk and (iii) optically-induced afterpulsing. While the internal crosstalk and afterpulsing involves photon transport within the SiPM, the external cross-talk photons escape from the surface of one SPAD and potentially: (i) reflect back into the SiPM at the surface coating interface and trigger avalanches in neighbouring SPADs, (ii) transmit through the SiPM surface coating. Since some of the future multi-ton dark matter and neutrinoless double beta decay experiments are choosing SiPMs as photosensors, the external crosstalk can be a significant background due to each SiPM's tendency to trigger a nearby one. This mechanism may cause detector background and reduce the accuracy of photo-electron resolution for high photo-electron events, leading to a degradation in the position and energy reconstruction.
To quantify the systematic effects which deteriorate the overall performance of such detectors, a study on SiPM secondary photon emission was conducted. It determined the absolute secondary photon yield equal to the number of photons emitted per charge carrier ($\gamma/e^-$) using spectroscopy. The photon yields were calculated at 163 K and 87 K to mimic the SiPM performance at liquid Xenon and liquid Argon temperatures. In this talk, I will summarise the spectroscopy technique and data analysis used to quantify the secondary photon yield at these temperatures.
Dark Matter Detection is an important issue in both cosmology and particle physics. WIMPs (Weakly Interacting Massive Particles) are one of the most promising candidates for dark matter and are being studied worldwide. The XENON group has the most sensitive detector in the world.
On the other hand, the DAMA/LIBRA group reports the annual modulation using NaI(Tl) with lower sensitivity than the XENON group. Hence verification is essential. Moreover, verification of the annual modulation of the DAMA/LIBRA group requires NaI(Tl) crystals with backgrounds comparable to those of the DAMA/LIBRA group.
PICOLON (Pure Inorganic Crystal Observatory for Low-energy Neut(ra)lino) aims to use ultra-pure NaI(Tl) crystals to search for dark matter and to verify the annual modulation reported by the DAMA/LIBRA group.
In the 2020 report, crystals (Ingot#85) with backgrounds concentration comparable to DAMA/LIBRA were developed. In this presentation, we report the background and sensitivity of a new PICOLON crystal (Ingot#94) developed using the Ingot#85 purification method.
KATRIN (Karlsruhe Tritium Neutrino Experiment) aims to measure the neutrino mass by analyzing the endpoint region of a Tritium spectrum using a high-luminosity source and a high-resolution MAC-E filter technique. KATRIN holds the current best limit on the neutrino mass of 0.8 eV, coming from the joint analysis of the first two measurement campaigns.
After KATRIN’s data taking, a detector upgrade, called TRISTAN, is planned. The choice for this new detector is a matrix of Silicon Drift Detectors (SDDs) made of 9 modules with 166 pixels each.
KATRIN, equipped with the TRISTAN detector, has the potential to perform a high-statistics differential measurement deep into the Tritium β spectrum and thus enable the search for sterile neutrinos in the keV-range, candidates to be Dark Matter particles. The existence of these particles would lead to a kink in the β spectrum.
In order to search for this small signature an accurate model of the whole spectrum is needed. In particular, keV electrons can lose part of their energy by interacting with several elements of the beamline, leading to spectral distortions.
In this poster, I will provide an overview of the status and the challenges of a model for the whole Tritium differential spectrum.
Sterile neutrinos are a possible extension of the Standard Model of particle physics. If their mass is in the keV range, they are a suitable dark matter candidate. One way to search for sterile neutrinos in a laboratory-based experiment is via tritium beta decay. A sterile neutrino with a mass up to 18.6 keV would manifest itself in the decay spectrum as a kink-like distortion.
The Karlsruhe Tritium Neutrino (KATRIN) experiment currently investigates the endpoint region of the tritium beta-decay spectrum to measure the effective electron anti-neutrino mass. The main objective of the TRISTAN project is to extend this energy range to measure the entire beta-decay spectrum. To this end, a novel multi-pixel silicon drift detector and readout system is currently being developed which enables the search for sterile neutrinos in the keV-mass range. This contribution will give an overview on the design and development of the new detector and show first test measurements of a detector module.
This work is supported by BMBF (05A17PM3, 05A17PX3, 05A17VK2, 05A17WO3), KSETA, the
Max Planck society, and the Helmholtz Association. Moreover, this project has received funding
from the European Research Council (ERC) under the European Union Horizon 2020 research
and innovation program (grant agreement no. 852845).
Germanium detectors have been widely used for both dark matter and neutrino-less double beta decay experiments due to its high energy resolution, low threshold and working at medium-low temperature. Hence large scale experiments up to ~ 1t detectors have been proposed, including LEGEND and CDEX. In order to achieve best performance, readout electronics, especially the front-end electronics should be mounted as close to the detector as possible. Custom designed ASICs (Application Specific Integrated Circuit) are demanded to satisfy the stringent requirement for low noise, low mass, highly integration and operation at cryogenic temperature. This paper will introduce the progress on the development of ASICs for HPGe detectors, including a low noise and wide dynamic range preamplifier and SCA (switched capacitor array) based waveform sampling chip with on-chip digitizer. A noise level of 108 eV FWHM has been measured with a 0.5 kg HPGe detector. Detailed chip design and test results will be present.
The Cryogenic Underground Observatory for Rare Events (CUORE) is the first tonne-scale experiment using cryogenic calorimeters. The detector is located underground at the Laboratori Nazionali del Gran Sasso in Italy and consists of 988 TeO2 crystals operated in a dilution refrigerator at a base temperature of about 10 mK. Thanks to the large exposure, sharp energy resolution, segmented structure and radio-pure environment, CUORE provided the most sensitive exclusion limit of the neutrinoless double beta decay of 130Te. The same features offer a unique opportunity to search for other beyond Standard Model processes including interactions of dark matter candidates, such as Solar Axions and WIMPs, in the CUORE crystals. We expect that these events will deposit a lower amount of energy than the neutrinoless double beta decay. Thus, we are working forward to demonstrate the potentiality of the CUORE detector technology in the keV region and profit from the very large amount of data collected so far (2 ton yr of exposure) to search for dark matter evidences.
The most promising strategy for demonstrating the Majorana nature of neutrinos is to observe neutrinoless double beta decay (0$\nu\beta\beta$). Measurement of the 0$\nu\beta\beta$ lifetime will provide direct insight into the absolute mass scale of neutrinos and probe the neutrino mass ordering. The next generation of 0$\nu\beta\beta$ experiments targets to probe the inverted mass ordering (IO) and enter the normal ordering (NO) regions. Estimation of the experimental specifications and their cost-effectiveness is becoming increasingly important as these experiments generally require tonne-scale of enriched isotopes and decade-long efforts to realize. We perform a quantitative study of the projected experimental sensitivities in terms of the discovery potentials $-$ prior to the experiments are performed. The sensitivity of counting analysis is derived with complete Poisson statistics and compared with its continuous approximation. Additional measurable signature such as energy can boost the sensitivity and this is incorporated via a maximum likelihood analysis. The roles and effects of uncertainties in background predictions are examined. The results reinforce and quantify the vital role of background suppression in future 0$\nu\beta\beta$ projects with sensitivity goals of approaching and covering NO.
Reference
M. K. Singh, H. T. Wong et al., Phys. Rev. D 101, 013006 (2020).
The AMoRE collaboration is engaged in experiments aimed at detecting neutrinoless double beta decay of 100Mo. The experiments utilize large molybdenum-based scintillating crystals with cryogenic sensors. The forthcoming AMoRE-II phase will use large cylindrical Li$_2$MoO$_4$ (LMO) crystals with diffusive surfaces, which helps to reduce the crystal preparation time significantly. Despite the increased mass of these crystals, 6 cm (D) x 6 cm (H) in dimensions, they have performed similarly to the previous 5 cm (D) x 5 cm (H) LMO crystals in various tests. The diffusive surfaces of the LMO crystals have improved the discrimination between alpha and beta/gamma particles through pulse shape discrimination (PSD) analysis, despite the slower signal compared to polished crystals. We also investigated muon events, which showed two bands in the PSD parameter (rise time) of the 6 cm LMO crystal with polished surfaces. Developing detectors with LMO crystals required optimizing crystal and environmental setup conditions and utilizing pulse shape analysis due to the lower scintillation light yield compared to CaMoO$_4$ (CMO) crystals used in previous phases. We will present detailed information on the preparation and results of the AMoRE-II R&D experiment.
The Jiangmen Underground Neutrino Observatory (JUNO), a 20 kton multi-purpose low background liquid scintillator detector, was proposed primarily to determine the neutrino mass ordering. For the sake of suppressing the radioactivity from the surrounding rocks and tagging the cosmic muons, the central detector is submerged in a water Cherenkov detector which is filled with 35 kton ultrapure water and equipped with 2400 20-inch MCP-PMTs. Strict requirements are put forward for the intrinsic radioactivity of the ultrapure water, i.e., the radon concentration should be less than 10 mBq/m3. As the progenitor of 222Rn, the concentration of 226Ra should also be precisely measured and kept well below 10 mBq/m3. In this poster, the details of two measuring systems, optimized to achieve a sensitivity of 1mBq/m3 for the radon concentration in water and of 10μBq/m3 for the radium concentration in water, will be described and discussed.
The Accelerator Neutrino Neutron Interaction Experiment (ANNIE) is a 26-ton gadolinium doped water Cherenkov detector with a submerged water-based liquid scintillator filled vessel. It is on-axis of the Booster Neutrino Beam (BNB) at Fermilab, and its main physics goal is to measure the neutrino cross-section which will improve the systematic uncertainties of next-generation long-baseline neutrino experiments. The first such measurement will be the final state neutron multiplicity of neutrino-nucleus interactions in water. ANNIE is also the first large-scale high energy physics experiment to deploy multiple Large Area Picosecond Photodetectors (LAPPD), a novel photon detector technology with a timing resolution of <100$\ $ps and a sub-centimeter spatial resolution which will help to improve the vertex reconstruction. This poster will give an update on the status of the LAPPD deployment as well as first results from neutrino beam induced events recorded by the LAPPDs.
Excess energy stored in NAI(Tl) crystals can cause spontaneous luminescence, and exposure to red light can release thermally induced luminescence. We can assume that stored energy can spontaneously be transformed into heat. We know that energetic particles can produce energy-storing states, and we can assume that interactions with practice can release stored energy either as luminescence or heat. Environmental factors also can affect the accumulation and release of stored energy. We discussed several scenarios of how these effects can lead to background luminescence modulations. This work was performed under the auspices of the U.S. Department of Energy by Lawrence Livermore National Laboratory under Contract DE-AC52-07NA27344. LLNL-CONF-849050.
The dark photon emerges as an additional gauge boson in a U (1) Standard Model extension and is coupled to the ordinary photon via kinetic mixing. To investigate the energy band from 6-8 eV, where photons are highly absorbent due to molecular oxygen with an absorption length on the order of cm at atmospheric pressure, we developed the Ultraviolet Range Initiated photons from Dark-photons in Ambient (URIDA) Experiment, motivated by other work. In order to minimize attenuation, the detection system was housed in a vacuum chamber. We constructed our detector system using low dark rate photomultipliers that are sensitive at these energies and included an aluminum reflector similar to the FUNK experiment to enhance collection. Results on performance and preliminary sensitivity will be reported
Cryogenic phonon detectors with superconducting thermometers achieve the strongest sensitivity to light dark matter recoils in current direct detection dark matter searches. In such devices, the temperature of the thermometer and the bias current in its readout circuit need careful optimization to achieve optimal operation conditions. This task is not trivial and has to be done manually by an expert, which makes the simultaneous operation of many detectors challenging. We simulated the detector response as an OpenAI Gym reinforcement learning environment and finetuned it to resemble the behavior of three CRESST-III detectors currently operated in run 36 of the experiment. In the simulation, we test the capability of a Soft Actor-Critic agent to perform the optimization task. Furthermore, we report on a measurement interval in February 2023, during which we tested our method live on the identical detectors running in the CRESST underground setup at LNGS. Finally, we discuss large pre-trained models that can perform the optimization task without the necessity for training on individual detectors. Our method can improve the scalability of multi-detector setups.
Subterrestrial neutron spectra show weak but consistent anomalies at multiplicities ~100 and above [1-3]. The data of the available measurements are of low statistical significance [4] but indicate an excess of events not correlated with the muon flux. The origin of the anomalies remains ambiguous, but it could be a signature of WIMP annihilation-like interaction with a Pb target. In the presentation, we’ll outline a model consistent with this hypothesis. We use an extended Standard Model approach called the Radiation Gauge Model (RGM). The RGM identifies the scalar neutrino-antineutrino wave function component of WIMP DM responsible for the weak interaction leading to annihilation with ordinary matter. The model assigns neutrino-(target)nucleon CC (charged current) transitions to the observed anomalies. For example, an 8 GeV WIMP particle annihilating Pb nucleus requires 3.25 GeV excitation to destroy or fragment the Pb into neutrons and protons, which further undergo (n, xn) and (p, xn) reactions in the massive Pb target. The outgoing weak interaction leptons (e, mu, tau, and neutrinos) take the remainder of the energy (4.75 GeV). If the existence of the anomalies is confirmed and the model interpretation is positively verified, this will be the first terrestrial Indirect Detection of Dark Matter.
[1] https://doi.org/10.22323/1.395.0514
[2] http://doi.org/10.1088/1742-6596/2156/1/012029
[3] https://doi.org/10.1016/j.nima.2022.167223
[4] TAUP abstract #166
CRESST is an experiment for the direct detection of dark matter, situated at Laboratori Nazionali del Gran Sasso (LNGS) in Italy. It is capable of detecting nuclear recoils down to 10 eV with an impressive sensitivity in the sub-GeV mass region. This is achieved by using cryogenic scintillation crystals as target materials. To separate background from signals a two-channel approach, measuring light and phonos, is utilized. However, the separation capability is poor in the low energy region and it is challenging to distinguish between dark matter interactions and $\beta$, $\gamma$ or $\alpha$-particles.
The background components are considered via simulations with 'ImpCRESST', a Geant4 based simulation code, which is continuously adapted to the setup of CRESST. At the current state, the CRESST background model only considers bulk contaminations and a flat detector surface.
This contribution presents possible effects of surface contamination with radiogenic elements, in combination with the influence of the surface roughness of the detector crystal itself. Because of nuclides decaying inside the crystal in the vicinity of the surface, it is possible that only a share of the energy is placed inside the detector.
As a result, higher energy events can leak into the lower energy range and may affect the simulated background. Since default Geant4 is not capable of simulating a rough surface an extension is developed and the impact of different roughness configurations is studied.
Cryogenic Observatory for SIgnatures seen in Next generation Underground Searches (COSINUS) will use cryogenic sodium iodide (NaI) calorimeters to search for dark matter. Recently, the construction of an underground facility at Laboratori Nazionali del Gran Sasso (LNGS) for COSINUS has been completed. The features of the COSINUS facility allow for a low background environment for rare event searches. This facility will house a dry dilution refrigerator, which will sit in a drywell inside a water tank. The water tank will be instrumented with photo multiplier tubes and serve as an active muon veto. Above the water tank, a clean room will allow for a clean environment for detector maintenance and installation. A vibrationally decoupled building next to the water tank will provide access to the clean room and hold a control room and maintenance rooms.
The axion was initially posed as a solution to the CP problem of QCD, but axion-like particles (ALPs) also arise in string theory and are a dark matter (DM) candidate. Most laboratory axion searches concentrate on the 0.001-0.1 meV mass range, however there is growing interest in heavier (DFSZ) axions (above 10 meV) which avoid the cosmological domain wall catastrophe[1] and may explain stellar energy losses beyond those accounted for by neutrino emission[2].
Here we describe new laboratory searches for axions performed at EuXFEL. These are sensitive to an axion/ALP mass range including 1 meV-1 eV, which is unconstrained by astrophysical arguments if axions constitute DM. Similar searches were previously performed on a 3rd generation synchrotron[3]; however limited flux prevented those experiments probing down to DM relevant couplings. This work is the first step in developing a platform with improved sensitivity due to an increase in brightness by $\sim10^{10}$ when using EuXFEL. Initial work has confirmed previous bounds on the axion-photon coupling[3] and considered a previously unexplored axion mass range. In future we expect to probe down to the coupling in the keV mass range for which QCD axions can be DM.
[1]K.Beyer & S.Sarkar arXiv:2211.14635v5. (2023)
[2]M.Giannotti+ JCAP 2017.10 (2017)
[3]T.Yamaji+ Phys.Lett.B 782, 523–527 (2018)
Funded by the UK EPSRC (EP/X01133X/1 & EP/X010791/1). SS & GG are members of the QSHS consortium funded by the UK STFC (ST/T006277/1).
We developed a low threshold detector for low mass dark matter search with a CaF2 crystal and an MMC readout. The detector was assembled to make a direct metal-metal contact between an MMC sensor and a phonon-collector film on the crystal. This new absorber-sensor geometry resulted in a signal rise-time of about 100 us and a detection threshold of about a few tens of eV. We present the detector performance and the results of an above-ground measurement for the direct detection of low-mass dark matter
The next generation of skipper-CCD experiments for rare-event searches will bring new challenges for the detector packaging and read-out. Scaling the active mass and simultaneously reducing the experimental backgrounds in two orders of magnitude will require a novel high-density Silicon-based package, that must be massively produced and stored. In this work, we present the design, first production, and testing of a 16-channel Silicon package, along with the outlook for the next steps towards producing 1500 wafers that will add up to a 10 kg skipper-CCD detector.
The Cryogenic Rare Event Search with Superconducting Thermometers (CRESST) experiment aims for the direct detection of dark matter (DM). In the current low-mass DM search, a low energy threshold and a high resolution at low energies are crucial for exploring the parameter space. In the most recent CRESST Phase III, alongside hardware changes, the energy threshold could be improved using a different analysis approach based on the optimum filter method, which reduces the noise contribution to the signal, resulting in an optimized signal-to-noise ratio. This allows the experiment to be one of the leading ones in probing sub-GeV DM masses. In this contribution the optimum filter method has been tested for performance and improvement using additional digital filtering and calibration methods.
The Cryogenic Rare Event Search with Superconducting Thermometers (CRESST) is one of the most sensitive experiments when it comes to the direct detection of light dark matter via nuclear recoils.
At low recoil energies below 100eV, the sensitivity is currently affected by the presence of a sharply increasing event rate below a few hundred eV for which dark matter as an origin has already been ruled out. This low energy excess (LEE) is not only observed in all CRESST detectors but other experiments encounter similar issues, making these observations relevant for the whole field, without a clear idea about its origin so far.
We will present the progress we made toward a model of the LEE that works for all CRESST detectors while using as few parameters as possible. We use two-dimensional unbinned likelihood fits for fitting time and energy simultaneously.
The studies cover our most recent data-taking run, including cycles where the cryostat was warmed up and cooled down several times to investigate temporary rises in the low energy event rate that have been observed to occur after such warm-ups.
Direction-sensitive detector with solid-state target is expected to have higher sensitivity for WIMPs window compared to conventional dark matter search using Tl:NaI and other scintillators. ZnWO4 was reported to have anisotropic of light outputs for each crystal surface excited by alpha rays. In this study, we evaluated such anisotropic effect for several crystals such as PbWO4 with a size of 10 cm $\times$ 10 cm $\times$ 10 cm $\times$. Since these crystals have no cubic structure, crystal orientations did not correspond to the cutting surface. PbWO4 was found to have the different light output and $\alpha$/$\gamma$ ratios for each surface as well as ZnWO4 had. Moreover, such samples were irradiated with single electron and proton, and the result of proton irradiation showed the anisotropic effect. On the other hand, the difference was not observed clearly for electron irradiation.
Multiple viable theoretical models predict heavy dark matter particles with a mass close to the Planck mass, a range relatively unexplored by current experimental measurements. We conducted a blind search for signals from Multiply-Interacting Massive Particles (MIMPs) in XENON1T, whose unique track signature allowed a targeted analysis with only 0.05 expected background events from muons. We observed no signal candidate events in the search data with a total exposure of 219.4 days. In this poster, we will present the search strategy and the new constraints on spin-independent and spin-dependent interactions of dark matter particles with masses close to the Planck scale.
IAXO aims to detect solar axions as they are back-converted into X-rays along a strong magnet pointed towards the sun. Excellent spectroscopic performance, high X-ray absorption efficiency at and below 10 keV, and great potential for ultra-low background operations are features of silicon drift detectors that could facilitate this endeavour. TAXO is a two-stage project which aims to demonstrate ultra-low background X-ray detection at shallow depth, exploiting material properties and a novel all-semiconductor active-shield concept. Our poster displays the progress towards an ultra-low background semiconductor detector for IAXO, including first background results. This work is supported by the Semiconductor Laboratory of the Max Planck Society, the Excellence Cluster ORIGINS, the SFB1258, and the Bavarian Academy of Sciences and Humanities.
The XENONnT experiment, located underground at the Laboratori Nazionali del Gran Sasso, uses a total of 8.6t of high-purity liquid xenon to directly search for WIMP (weakly interacting massive particle) dark matter using a dual phase time projection chamber. Most of the low-energy electronic recoil background is caused by intrinsic contamination of the xenon by Rn-222 with a half-life of 3.8d, which is continuously emanating from the detector materials.
For the reduction of this background, a high-flow online radon removal system was designed and constructed (M. Murra et al, Eur. Phys. J. C 82 (2022) 1104), which uses cryogenic distillation based on the difference in vapor pressure between radon and xenon. The system can be operated in parallel in two modes: At a flow rate of 200 slpm, liquid xenon is extracted from the detector and passed through the system. The cleaning time constant, which only corresponds to one mean lifetime of Rn-222 (5.5d), results in a reduction in radon concentration by a factor of two. An additional extraction of 25 slpm of gaseous xenon provides another reduction factor of about two. With the combined operation of both modes, an extremely low Rn-222 activity concentration of < 1 µBq/kg is achieved, the lowest of any xenon dark matter experiment.
This contribution shows the basic concept of the XENONnT radon removal system and the performance of the system in the XENONnT experiment.
The project is funded by BMBF under contract 05A20PM1.
The XENON collaboration employs dual-phase xenon time-projection chambers to search for weakly interacting massive particles (WIMPs) and other rare processes. In order to achieve high sensitivity to the WIMP-nucleon cross-section, radioactive contaminants must be carefully monitored and suppressed. One impurity particularly difficult to remove is krypton, presenting a significant challenge as signals induced by the β-decay of $^{85}$Kr leak into the ROI for dark matter searches. A cryogenic distillation column was developed for the XENON1T experiment, lowering the $^\text{nat}$Kr/Xe concentration and thus making the $^{85}$Kr background subdominant compared to the contamination from the radon decay chain.
During preparation for the XENONnT experiment, the xenon inventory was cleaned and a $^\text{nat}$Kr/Xe concentration of $(56\pm 36)\,$ppq was reached with an online distillation mode for the first sience run of XENONnT. This poster will present the cryogenic krypton distillation column and demonstrate its use cases with the current XENONnT experiment.
The project is funded by BMBF under contract 05A20PM1.
Recently the sub-GeV dark matter (DM) mass region has started to be probed. To explore this region, detectors with a low energy threshold are required. Recent developments in the production of diamond crystals allow for high-quality large-mass diamonds that can be used as DM detectors. Thanks to their superior cryogenic properties, diamond detectors can reach an energy threshold in the eV range. In this contribution the realization of the first low-threshold cryogenic detector that uses diamond as an absorber for astroparticle physics applications will be reported. Two diamond samples instrumented with a W-TES have been tested, showing transitions at about 25 mK. The performance of the diamond detectors will be presented highlighting the best performing one, reaching an energy threshold of 16.8 eV. Finally, the dark matter results that could be achieved with this measurement will be shown.
The ultra-clean radon-free four cylinder magnetically-coupled piston pump is a high performance gas displacement pump interesting for the usage in low background experiments dealing with noble gases as target material. Due to its low radon emanation and special cleanliness in terms of out-gassing, in addition to the high and stable performance, the four cylinder pump is currenlty operated as a xenon gas compressor at the novel radon removal system of the dark matter experiment XENONnT.
The four cylinder pumps connected in parallel feature a phase-shifted synchronization of their movements in order to increase the flow and to provide long-term performance combined with low output pressure and flow fluctuations. A custom-made programming of the synchronization gives the possibility to operate the system with different configurations and to monitor the status of each pump during the operation. In this poster, the function and the operation experience with this magnetically-coupled piston compressor are presented. This research was partially supported by BMBF under the contract 05A20PM1.
The world-leading dark matter direct detection experiment XENONnT exploits a TPC-instrumented liquid Xenon active target of about 5.9 t.
In order to enhance the light collection efficiency, the TPC volume is delimited by diamond-tip shaved PTFE panels.
Radioactive isotopes contaminating these panels, directly in contact with the Xenon active mass, are responsible for generating the “surface background”.
In particular, electrons and gammas originating from the decaying 210Pb, implanted in the PTFE when air-exposed due to the radon plate out phenomenon, contribute to the background budget for the WIMP signal search.
Differently from the other electronic recoil background sources due to the electrons collection on the PTFE panels, these events are characterized by a reduced ratio between ionization and scintillation signals, mimicking WIMP nucleus scattering events.
Traditionally, in order to reduce this background contribution, a fiducial volume cut is applied limiting the experimental exposure and hence the WIMP signal sensitivity.
The study presented probes the feasibility of implementing a physics-driven surface background model that could in principle allow the extension of the fiducial volume increasing the experimental exposure for the WIMP search.
Moreover, by exploiting the Flamedisx modelling and fitting framework the discovery power in case of detected signal is enhanced.
For over twenty-five years, the DAMA/LIBRA experiment observes an annual modulation signal that is consistent with a dark matter explanation. Under the standard halo scenario, this signal is in tension with the null results observed by other searches that utilize different target detectors. The COSINUS experiment will perform a model-independent cross-check of the DAMA/LIBRA result by using the same target material, NaI crystals, operated as scintillating calorimeters. COSINUS is currently under construction at Laboratori Nazionali del Gran Sasso, Italy. In this low background underground facility, the detectors are placed at the centre of a 7$\times$7 m cylindrical water tank, which acts as a passive shield against the ambient and cosmogenic background. However, muon-induced neutrons, created near the detector, can mimic a potential dark matter signal. Therefore, an active muon veto system is required to identify and remove these events. We report on the results of a design study for an active water Cherenkov muon veto. This study optimizes the design for tagging muons while mitigating the overall background trigger rate. To achieve this, comprehensive Monte Carlo simulations were conducted to investigate the impact of various factors including: trigger conditions, photomultiplier tube arrangements, foil reflectivity, and the size of the optically invisible region in the water tank.
MADMAX, the MAgnetized Disc and Mirror Axion eXperiment, is a novel dielectric haloscope concept to detect the axion in the mass range 40-400 ueV through enhancement of the inverse Primakoff process. The discovery of the axion could solve both the strong CP problem, fundamental in particle physics, and the dark matter problem. Currently, MADMAX uses a prototype system called CB-100 to understand the different challenges of this novel concept at frequencies in the order of 20GHz at room temperature. One of the most urgent tasks is to operate the experiment at cryogenic temperatures, where the sensitivity to the QCD axion would be significantly higher. In this poster, I first justify why this effort could be interesting for other applications inside and outside astroparticle physics. Then, I explain the challenges and progress in accomplishing a cold calibration of CB-100. Finally, I show the projected sensitivity enhancement from this upgrade in the next MADMAX dark matter search campaign.
The upgrading rare event detection experiments has become increasingly urgent with updating the performance of the electronics. In the next phase of China Dark Matter EXperiment (CDEX), the electronics have been designed barely immersing in 6.5 m shielding thickness of liquid nitrogen with detector crystal, and the flexible electronic substrate (FES) composed electronics are required to be high adhesion, low-temperature resistance and low-background. Polytetrafluoroethylene (PTFE) is widely recognized with low-background, high dielectric properties. To solve the problem of poor surface adhesion, we propose a new method for analyzing the surface adhesion of polymers, which provide direct insight into the influence of ion implantation on the polymer surface adhesion. The adhesion of self-developed FES after soaked in liquid nitrogen for 20 days is not less than 0.67 N/mm, demonstrating good low-temperature resistance. In addition, the dissipation factor of the self-developed FES is less than 0.003 at 173K, which is better than 17 times that of commercial FES products. Furthermore, the screened low-background PTFE and PTFE composite films can be designed as CDEX partition materials. In conclusion, we studied the structure-activity relationship of ion implantation modification polymer surfaces, which provides a theoretical basis and practical example for the development of high adhesion, low-temperature resistance and low-background FES.
Magnetically-levitated superconducting particles have potential as ultrasensitive inertial sensors for dark matter detection. They can be highly-isolated from their surroundings, in ultrahigh vacuum at cryogenic temperatures, and confined in dissipationless traps. They can be coupled to superconducting quantum circuits, offering the potential for sensing the particle motion beyond the standard quantum limit.
We have been developing this platform for performing quantum experiments using macroscopic (micrometer-scale) particles. By scaling-up to centimetre-scale particles, it can make an excellent sensor for impulses from dark matter near the Planck scale, and for ultralight dark matter candidates.
The Large Enriched Germanium Experiment for Neutrinoless $\beta \beta$ Decay (LEGEND) is an experimental program searching for the neutrinoless $\beta \beta$ decay of $^{76}$Ge. The experiment is designed to reach half-life sensitivity of $10^{28}$ years. To achieve such rare event rate requires a number of measures to reduce background due to more common phenomena. A Water-Cherenkov-Veto system acts for LEGEND-200 to actively reduce background. It uses photomultiplier tubes as light sensors in a water-tank covered with a reflective foil to increase the light yield inside the water volume. In this poster we present the working principle and data analysis of the current muon veto and discuss plans for its future improvements for the next experimental phase LEGEND-1000.
This work is supported by the U.S. DOE and the NSF, the LANL, ORNL and LBNL LDRD programs; the European ERC and Horizon programs; the German DFG, BMBF, and MPG; the Italian INFN; the Polish NCN and MNiSW; the Czech MEYS; the Slovak SRDA; the Swiss SNF; the UK STFC; the Russian RFBR; the Canadian NSERC and CFI; the LNGS, SNOLAB, and SURF facilities.
LEGEND-200 at LNGS is an experiment designed to search for neutrinoless double beta decay of Ge-76 by operating up to 200 kg of enriched Ge-detectors in liquid argon (LAr). To achieve ultra-low backgrounds, the LAr is instrumented to detect scintillation light emitted upon interactions with ionizing radiation, thus tagging and rejecting backgrounds. The LAr scintillation light is detected with wavelength-shifting fibers coupled to SiPM arrays. We demonstrate the high photoelectron (p.e.) resolution and low noise level of the SiPM signals. We also present the results of special calibration runs performed to determine the p.e. yield and background suppression factors. Maximized geometrical coverage and wavelength conversion efficiency result in a high p.e. yield, which in turn enables effective particle discrimination. We illustrate the suppression performance using K-lines and Ra–226 calibration data. Furthermore, we present the additional LAr DAQ trigger which allows the investigation of time-correlated backgrounds, such as BiPo-214 and muon-induced neutron captures on Ar-40. This, together with the particle discrimination capability, elevates the LAr instrumentation from a simple veto to a full-fledged detector.
This work is supported by: German MPG, BMBF, DFG; Italian INFN; Polish NCN, MNiSW; Czech MEYS; Slovak SRDA; European ERC, Horizon programs; Swiss SNF; UK STFC; U.S. DOE, NSF, LANL, ORNL, LBNL LDRD programs; Russian RFBR; Canadian NSERC, CFI; LNGS and SURF facilities.
The delayed decay of $^{77(\mathrm{𝑚})}$Ge, produced by neutron capture on $^{76}$Ge, is a potential background for the next generation neutrinoless double beta decay experiment LEGEND-1000 at the LNGS site. Based on Monte Carlo simulations, several mitigation strategies and suppression techniques have been proposed to identify and suppress this background [1,2,3]. So far, only weak experimental limits have been found on the production rate. We present new results from the GERDA experiment on the search for $^{77(\mathrm{𝑚})}$Ge by exploiting the isomeric state in $^{77}$As. Given the very similar configuration - bare germanium detectors in liquid argon - it serves as a benchmark for our LEGEND-1000 predictions. This research was supported by the BMBF through the Verbundforschung 05A20WO2 and by the DFG through the SFB1258 and the Excellence Cluster ORIGINS.
[1] C. Wiesinger et al., Eur. Phys. J. C (2018) 78: 597
[2] LEGEND-1000 pCDR, arXiv 2107.11462
[3] M. Neuberger et al., 2021 J. Phys.: Conf. Ser. 2156 012216
Neutrinos in the energy range from a few hundred MeV to several GeV are relevant for the study of neutrino oscillation by atmospheric neutrino observation and long baseline experiments. In this intermediate energy region charged-current quasi-elastic scattering (CCQE), single pion production, and deep inelastic scattering coexist with comparable contributions. The T2K experiment has been using CCQE events as the primary data sample to measure neutrino oscillations, but single pion production events are used as the signal in the recent analyses. Single pion production is crucial in the NOvA experiment and the future DUNE experiment as they measure the neutrino oscillation at higher energy than T2K with the longer baseline. Similarly, single pion production can be a background in proton decay searches at Super-Kamiokande and future experiments, including Hyper-Kamiokande. Therefore, it is important to understand the cross section and kinematics of single pion production to improve the precision of the neutrino oscillation parameter measurement and proton decay searches. For this purpose, we evaluated a new model for single pion production, called the dynamical coupled-channels model (DCC, T. Sato et al.). We compared it with the Berger-Sehgal model, currently used in the NEUT neutrino interaction generator and past experimental data sets. We also mention the implementation of electro-pion production using the same model. The results and future perspectives will be presented.
The KATRIN experiment aims to measure or exclude the effective
electron neutrino mass $m_\nu$ down to 0.2 eV/$c^2$ (90 % C.L.) by measuring
the tritium beta spectrum near its endpoint $E_0$, and performing a fit
including the parameters $E_0$ and $m_\nu^2$. Since these are highly correlated,
a systematic shift influencing the obtained neutrino mass would be
visible in the endpoint and thus tritium $Q$ value. $Q$ has been derived from the mass difference of $^3$He$^+$ and $^3$H with 70 meV precision (cf. PRL. 114, 013003 (2015)).
This has not been applicable to KATRIN so far due to uncertainty of the measured plasma potential in the tritium source.
The KATRIN $Q$ value can also be determined by absolute calibration
with conversion electron lines from co-circulating $^\mathrm{83m}$Kr.
This is however limited by nuclear gamma transition
energy uncertainties of $^\mathrm{83m}$Kr to 0.5 eV accuracy. The excited
nucleus of $^\mathrm{83m}$Kr decays in a two-step cascade of 32.2 keV and 9.4 keV
highly converted gamma transitions.
In new measurements performed at KATRIN, a large set of conversion electron
lines, including a new line, was measured with a gaseous and a condensed
krypton source. Following the method described in EPJ C 82
(2022) 700, the $^\mathrm{83m}$Kr gamma transition energies can be determined,
which can allow for reduction of tritium $Q$ value uncertainty to
~0.1 eV. This poster presents the status of the analysis.
Supported by BMBF under contract number 05A20PMA.
The coherent elastic neutrino-nucleus scattering (CEvNS) process in reactor neutrino experiments has yet to be observed. We are proposing to use a dual-phase argon time projection chamber (TPC) detector with a fiducial volume of several hundred kilograms to measure the reactor neutrino CEvNS. The location of this experiment is chosen to be at the Taishan nuclear power plant in China, where the thermal power is 4.6 GW and the expected neutrino flux at a distance of 35 m from the reactor core is 6×10^{12}cm^{−1}s^{−1} .
The dominant backgrounds of this experiment are from the cosmic rays. Therefore, to optimize the size of the detector, we simulate the muon-induced responses to evaluate the live-time during the operation of this experiment. Furthermore, we perform simulations of cosmogenic isotopes and the intrinsic background of the detector using an optical model to estimate the pile-up rate of the detector.
High-purity germanium detectors are used in the search for rare events such as neutrinoless double-beta decay, dark matter and other beyond Standard Model physics. Due to the infrequent occurrence of signal events, extraordinary measures are taken to reduce background interactions and extract the most information from data. An efficient signal denoising algorithm can improve energy resolution and background rejection techniques, and help classify signal events. It can also help identify low-energy events where the signal-to-noise ratio is small.
In this work, we demonstrate the application of generative adversarial networks with deep convolutional autoencoders to remove electronic noise from high-purity germanium p-type point contact detector signals. Built on the success of denoising using a convolutional autoencoder, we investigate generative adversarial networks applied on autoencoders to further improve denoising and enable more realistic model training conditions. This includes training with unpaired simulation and real data, as well as training with only real detector data without the need of simulation. Our approach is not limited to high-purity germanium detectors; it is broadly applicable to other detector technologies in the particle astrophysics community and beyond.
AMoRE is a series of experimental searches for the neutrinoless double beta decay of 100Mo using molybdate-based crystals, such as 40Ca100MoO4 and Li2100MoO4. AMoRE phase-II aims to use 400 bolometric crystals that contain a total of 120 kg of enriched 100Mo with an internal radioactivity background level that is below 510-6 count/kg/keV/year in the region of interest. To reach this level of purity, background levels of radioactive contaminants from thorium and uranium chains in the materials used for the crystal production must be reduced to below Bq/kg. This work will describe the purification method and technology for mass production of low-radioactive, high-purity 100MoO3 powder for the AMoRE-II crystals. We will present results from ICP-MS and HPGe array analyses of the purified powders that confirm the effectiveness of the radioactivity reduction.
Double electron capture (DEC) is a rare nuclear decay process in which two orbital electrons are captured simultaneously in the same nucleus.
The measurement of its two-neutrino emitting mode provides a new reference for calculating nuclear matrix elements, while the zero-neutrino emitting mode would demonstrate a violation of lepton number conservation.The two-neutrino DEC mode in 124Xe has been previously observed by the XENON1T experiment. For other nuclei, however, no significant signal was observed. For example, our target isotope of 112Sn, DEC to the excited state in 112Cd was searched using an HPGe detector, but no significant signal was observed. DEC to the ground state in 112Cd has not been conducted so far.
We propose an approach to search for the DEC mode to the ground state in 112Cd using gamma-ray Transition Edge Sensors (TES) with Sn absorbers.
The calorimetric (source = detector) configuration allows us to detect two X-ray or Auger electrons resulting from the 112Sn DEC mode with high resolution.
The state-of-the-art multi-pixel TESs increase the target amount, enhancing sensitivity.
In this presentation, we will present the demonstration of our search for the 112Sn two neutrino DEC using gamma-ray TES and future prospects.
Cosmic-ray muons that penetrate the Super-Kamiokande detector generate hadron showers in water, producing unstable radioactive isotopes through spallation reactions. These isotopes are major background sources for neutrino observation at MeV scale and for the search for rare events. While Super-Kamiokande has started observation using ultra-pure water in 1996, gadolinium was loaded with 0.011wt% in 2020 aiming for the observation of diffuse supernova neutrino background for the first time. In this study, we measured ${}^9$Li isotope generated by the muon spallation. ${}^9$Li has a lifetime of about 0.26 seconds and emit an electron and a neutron with a branching ratio of 50.8%. These pairs of an electron and a neutron are difficult to distinguish from the inverse beta decay reaction caused by an electron antineutrino, and therefore become major background for DSNB searches.
In the data analysis, we selected ${}^9$Li event candidates by searching for pairs of low energy events following cosmic-ray muons. Before the gadolinium loading, the Super-Kamiokande experiment had an energy threshold of about 8 MeV for searching for the decay electrons from ${}^9$Li. In this study, the threshold was lowered to 5 MeV for the measurement by the reduction of the accidental background with the gadolinium loading. In this presentation, we will report on the measurement method and analysis status.
The Advanced Mo-based Rare process Experiment (AMoRE) is an underground experiment that aims to detect the neutrino less double beta decay of $^{100}$Mo isotope. Reducing the detector background to as low as possible, ideally, zero level, is one of the key requirements of double beta decay experiments. Radioactive contaminants in the construction materials, such as $^{232}$Th and $^{238}$U daughters, are the most prevalent background sources in the experiments. The environmental fluxes of neutrons, muons, and gamma rays at the experimental site also contribute to the background levels.
The AMoRE-II aims to achieve a background level of 10$^{-4}$ events/keV/kg/year and is in preparation at the Yemi Underground Laboratory (Yemilab), located in the Handuk mine of Yemi mountain. To estimate the background conditions in the AMoRE-II, we conducted simulations using the GEANT4 Toolkit. These simulations focused on determining the background levels arising from external shield materials, detector modules and details nearby the detectors. We will present a detailed account of our various background simulations and estimate of the background levels within the region of interest.
I present studies on a deep convolutional autoencoder originally designed to remove electronic noise from a p-type point contact high-purity germanium (HPGe) detector. With their intrinsic purity and excellent energy resolutions, HPGe detectors are suitable for a variety of rare event searches such as neutrinoless double-beta decay, dark matter candidates, and other exotic physics. However, noise from the readout electronics can make identifying events of interest more challenging. At lower energies, where the signal-to-noise ratio is small, distinguishing signals from backgrounds can be particularly difficult.
I focus on the results of a recent publication from our group to demonstrate that a deep convolutional autoencoder can denoise pulses while preserving the underlying pulse shape well. Our research shows that a deep learning-based model is more effective than traditional denoising methods. I also highlight several studies on how the use of this autoencoder can lead to better physics outcomes through improvements in the energy resolution and better background rejection. Finally, I present extensions of this research that our group is working on. Our approach is straightforward to apply to other detector technologies and has great potential to be used in particle physics experiments as well as any other fields dealing with noisy one-dimensional signals.
Gauged $U(1)'_{L_\alpha-L_\beta}$ ($\alpha,\beta = e,\mu$ or $e, \tau$ or $\mu, \tau$) extension of the Standard Model results in a new $Z'$ boson, which, if ultra-light, mediates long but finite-range flavor-dependent neutrino-matter interactions. In $U(1)'_{L_e-L_\beta}$ ($\beta = \mu, \tau$) models, neutrinos interact with matter (electrons) directly via $Z'$ boson; however, in $U(1)'_{L_\mu-L_\tau}$ model, the interaction between neutrinos and ample matter (neutrons) is achieved through $Z-Z'_{\mu \tau}$ mixing. Such long-range interactions (LRIs) can hinder the neutrino oscillations, manifestations of which may be seen as the change in flavor composition of diffused astrophysical neutrino flux observed at the Earth. Considering major repositories of matter in the Universe, we constrain LRIs using projected measurements of neutrino flavor composition at the current and the future neutrino telescopes, assisted by the existing and projected measurements of mixing parameters by the present and next-generation neutrino oscillation experiments. In all three models, the constraints on the LRI potential by the 2040 IceCube-Gen2 projections is at-least $\sim 1/3$ times better than those by the 2020 IceCube estimates. Our estimates for 2040 by the IceCube-Gen2 experiment dominate over those from other planned experiments --Baikal-GVD, KM3NeT, P-ONE, and TAMBO.
The quest for the neutron Electric Dipole Moment (neutron EDM) started more than sixty years ago and is still one of the most important tasks faced by experimental physicists. The reason is that a non-zero value of this observable would violate both the parity symmetry and the time-reversal symmetry. Such a symmetry violation may help us to explain why the Universe is essentially made of matter and not of antimatter. The latest results of the neutron EDM measurement at PSI, where the highest sensitivity among all neutron EDM measurements made to date has been achieved, will be presented along with prospects for further development of the experiment. Furthermore, the measurement method used allows the search for dark matter candidates, i.e. mirror neutrons and very light axions - the results of these measurements will also be briefly presented.
Several extensions of the Standard Model predict the existence of exotic feebly interacting particles (FIPs) that would be abundantly produced by supernova (SN) explosions. Some remarkable examples of FIPs are sterile neutrinos, dark photons and axion-like particles, with the common feature of interacting with electrons and positrons. In this work we constrain the amount of electrons/positrons produced by SN explosions due to the decay of FIPs in the interstellar medium. We use local electron/positron measurements as well as keV-to-MeV gamma-ray data in different regions of the sky to constrain the inverse Compton and bremsstrahlung emissions from the injected electron population, and the data from the 511 keV line produced from the annihilation of positrons in the interstellar medium. We show that the strongest constraints come from the 511 KeV emission and improve the current constraints on FIPs thanks to the use of refined astrophysical models.
The ALPACA experiment is a new project aimed at observing UHE gamma rays in the southern hemisphere. The observation site is located at 4,740 meters above sea level on Mt. Chacaltaya in Bolivia. It consists of a surface air shower array of 401 scintillation detectors and a large-area water Cherenkov-type underground muon detector array. A small surface air shower array of the ALPAQUITA, a prototype of ALPACA, has been partially installed and has been in operation since 2022. The construction status and initial data analysis of ALPAQUITA will be presented.
The CRESST (Cryogenic Rare Event Search with Superconducting Thermometers) experiment aims to directly detect dark matter (DM) particles via their elastic scattering off target nuclei in scintillating CaWO$_4$ crystals.
One of the stable oxygen isotopes, $^{17}$O, has a nuclear spin of 5/2. Therefore, CaWO$_4$ crystals can be used for spin-independent and spin-dependent DM searches. Due to its low natural abundance of 0.038$\%$, a $^{17}$O enrichment of the CaWO$_4$ crystals will significantly increase the sensitivity of CRESST to spin-dependent DM interactions.
The CaWO$_4$ crystals used in CRESST have been grown in-house at the Technische Universität München (TUM) for many years, and have a lower level of radioactive impurities than any commercially available crystals.
Based on the experience in crystal growth at TUM, a process for the enrichment of CaWO$_4$ with $^{17}$O was developed. Two CaWO$_4$ crystals were enriched and their $^{17}$O content was measured by nuclear magnetic resonance spectroscopy at the Universität Leipzig. This contribution presents the concept and first results of the $^{17}$O enrichment and sensitivity predictions for the spin-dependent DM search with enriched CaWO$_4$ crystals in CRESST.
I will introduce our structured doctoral program, the International Max Planck Research School on Gravitational Wave Astronomy. Since its start in 2006 more than 160 PhD students graduated from our school. I will give an overview of our curriculum and how our early career researchers learn from each other with topics ranging from theory to experiments in gravitational wave astronomy. The whereabouts of those who graduated with a doctor’s degree is also shown.
We present a multiplexed analog readout electronics system for Skipper-CCDs based on an ASIC. It allows for sub-electron noise-level operation while maintaining a minimal number of acquisition channels. In addition, it requires low-disk storage and low-bandwidth data transfer with zero added multiplexing time during the simultaneous operation of thousands of channels. We describe the implementation and results of this system in a new instrument composed of 160 sensors operated with a two-stage analog multiplexed readout scheme. The instrument is a part of the R&D effort of the OSCURA experiment.
The welcome reception is scheduled directly at the venue in the arcade courtyard with canapés and drinks.
Searches for neutrinoless double beta decay provide the most sensitive probe of whether neutrinos are Majorana particles. Observation of this lepton number violating decay would have significant implications for the understanding the origin of neutrino masses and possibly the asymmetry between matter and antimatter in the early universe. I will review the worldwide experimental program aiming to detect this rare process, as well as recent theoretical developments.
Visible in the sky as a swath of stars, dust, and gas, the Galactic plane of the Milky Way has been observed in every wavelength of the electromagnetic spectrum, from radio waves to infrared, optical, x-rays, and gamma rays. This work presents the first observation of the Galactic plane in high-energy neutrinos. Within our Galaxy, high-energy neutrinos can be produced when cosmic rays interact at their acceleration sites and during propagation through the interstellar medium. Using a new sample of neutrinos with energies ranging from 500 GeV to multi-PeV, tests of a diffuse Galactic neutrino emission find a 4.5$\sigma$ rejection of the background-only hypothesis. This observation was enabled by machine-learning techniques that improved the selection efficiency and angular resolution of cascade-like neutrino events produced from charged-current $\nu_e$ and $\nu_\tau$ interactions and neutral-current interactions of all flavors in IceCube.
Whether the magnetic monopole (MM) exists is a long-standing question in particle physics.
It is postulated to be crucially related to the quantization of the electric charge. Under the framework of the Grand Unified Theory (GUT), a certain amount of MMs are produced during the splitting between strong and electroweak forces, which occurred very shortly after the big bang. Past efforts were focused on searching for such GUT-MMs using super-conducting coils and large low-background detectors, which demand ultra-low temperatures and an underground environment, respectively. In this talk, I will introduce a new experiment that searches for coincidental signals of MMs in a high-precision magnetometer and plastic scintillators.
The origin of dark energy is one of the greatest puzzles in modern physics. Amending general relativity by the so-called cosmological constant $\Lambda$ allows to describe an accelerated expansion. However, such a procedure would lead to a severe fine-tuning problem with many unresolved questions. Consequently, the existence of new hypothetical scalar fields has been postulated, which couple to gravity and can account for dark energy. Those new scalars generically lead to new interactions, so-called fifth forces and are theoretically well-motivated irrespective of their role for dark energy.
Many high precision table top experiments are in principle able to detect these fields. The theoretical and numerical analysis needed for the detection of several prominent fields is provided, with a main focus on the environment-dependent dilaton that arises in the strong coupling limit of string theory. The very first experimental constraints on the parameters of this model are presented. For this, data from the qBounce collaboration and Lunar Laser Ranging (LLR) is used. Furthermore, the expected exclusion plots for the CAsimir And Non Newtonian force EXperiment (CANNEX) soon to be realised in an improved setup are presented.
We present a new dark matter (DM) scenario intimately linked to the baryon asymmetry of the visible sector. We question one of the Sakharov conditions: baryon number violation. We provide a framework where the dark sector carries an opposite but precisely compensating baryon asymmetry to that of the visible sector, therefore conserving baryon number at all times. Within an effective field theory approach, we guide ourselves with the principle of baryon number conservation. We show that such a scenario is compatible with all observational constraints. We predict a thermal, light DM candidate with a maximum mass of 5.03 GeV, but various asymmetry transfers can lead to even lighter asymmetric DM masses. By virtue of baryon number conservation, the DM candidate is absolutely stable. The portal between the dark sector and the visible sector is the so-called "neutron portal" and can be efficiently probed at colliders, with a possible link to early matter domination in the early universe. We also provide an explicit realisation of this scenario in a UV complete model, for which the asymmetry within the dark sector is generated by a leptogenesis-inspired mechanism. Generally, this scenario provides a novel way to link baryogenesis to dark matter, without the need of baryon number violation.
If the mediator in a given $2\to 2$ $t$-channel process is kinematically allowed to be on-mass-shell, the matrix element can become singular. For a massive and stable mediator, this singularity cannot be regularized using the usual methods, like Dyson resummation of self-energy contributions, or infra-red regularization schemes.
Models of particle dark matter are especially affected by this issue, as they by definition propose new massive stable particles. The singularity makes the relevant Boltzmanne quations impossible to solve.
In this talk, I will formulate a strict set of conditions for a given process to provide a singular contribution to the relevant Boltzmann equation. I will also describe the regularizatin method including interactions between the mediator and the surrounding medium, developed within the framework of thermal field theory. An application to an actual DM model will be presented.
The coherent elastic scattering of solar, diffuse supernova and atmospheric neutrinos on nuclei (CEνNS) represents the ultimate background for weakly-interacting massive particle (WIMP) detection in the GeV mass region. With the first detection of CEνNS only five years ago, these neutrinos represent a signal in themselves. Solar $^{8}\text{B}$ neutrinos are expected to be observed by the current generation of experiments, which would mark the first measurement of CEνNS from a natural source. XENONnT is one of these experiments. It has been taking science data since 2021 and recently published first results on low-energy electronic recoil signals and WIMPs. In this talk, I will present the experiment and outline the analysis effort for the first detection of solar $^{8}\text{B}$ CEνNS. Special emphasis is put on lowering the detection threshold of the detector and on the control of backgrounds near the threshold as prerequisites for a solar CEνNS detection. The current status of the search will be summarized.
The XENON collaboration primarily focuses on detecting the first direct evidence for the existence of Dark Matter (DM) in the Universe using xenon double-phase time projection chamber detectors. The latest iteration of XENON experiments, XENONnT, is currently accumulating scientific data at the LNGS underground laboratory in Italy with a target mass of 5.9 tonnes of liquid xenon. The exceptional level of radioactivity reduction achieved in XENONnT makes it suitable for a broad range of rare-events searches beyond DM. Among these searches, the exploration of double-weak decays is of great interest. In particular, the Xe124 double electron capture and two-neutrino/neutrinoless double beta decay of Xe136 represent promising channels to investigate in XENONnT. These processes exhibit an expected electronic recoil signal that can reach up to the few MeV energy scale, which falls within a different region of interest than the standard DM search. We have demonstrated the ability of xenon dual-phase TPCs to conduct such research, validating the expansion of the physics reach accessible by this detector technology. This presentation will cover the latest results and current status of high-energy searches with the XENONnT experiment.
The PandaX-4T experiment, located at the China Jinping Underground Laboratory, is currently running a dual-phase xenon time projection chamber with 3.7 tonne of liquid xenon target. Benefitting from the 2400-meter overburden and the careful selection of detector materials, the PandaX-4T experiment has achieved an extremely low background level. Although originally designed as a dark matter detector focused on the O(keV) energy region, the PandaX-4T detector also shows a great performance in the O(MeV) energy region, leading to opportunities of other rare-event searches, for example the neutrinoless double-beta decay of Xe-136 nucleus. In this talk, I will present the recent progress of extending the data analysis in the PandaX-4T experiment from O(keV) to O(MeV) energy region, including physics results of search for double-weak decays of different xenon isotopes as well as solar pp neutrino scatterings.
Detectors based on Liquid Argon or Xenon Time Projection Chambers have been successfully employed in several neutrino and DM experiments.
We propose an alternative method of exploiting the same targets, based on the imaging of their scintillation light, eliminating the dependency on the slow charge collection.
By capturing "pictures" of the LAr (or LXe) scintillation light emission, we aim to reconstruct both event topologies and energy deposition.
Several challenges must be overcome in order to successfully demonstrate this novel approach: the performance of photon detectors and conventional optical elements in the relevant spectral range is limited; thousands of photosensor channels in dense matrices must be read out in cryogenic conditions; a sufficiently wide and deep field of vision is needed to maximize the fiducial volume.
We plan to adopt this technique in GRAIN (Granular Argon for Interaction of Neutrinos): a 1-ton LAr target, part of SAND at the DUNE Near Detector complex.
The current design of GRAIN, its physics goals, the development of its optical elements and image reconstruction algorithms, and preliminary results from a cryogenic demonstrator will be presented.
A future liquid xenon TPC of the scale of many tens of tonnes, capable of detecting the atmospheric 'neutrino fog', will have sensitivity to multiple physics signals besides WIMP dark matter. Here we will discuss the opportunities for neutrino physics, including neutrino-less double beta-decay with $^{136}$Xe and double electron capture measurements of $^{124}$Xe, as well as astrophysical neutrino sources. Other exotic physics searches for solar axions, fractionally charged particles, multiply-interacting massive particles, and others, can also be conducted with a xenon observatory. The implications for the detector design and operations of these broader physics channels will be discussed.
MAGNETO-χ is developing sub-GeV dark matter detectors using diamond crystals and magnetic athermal phonon sensors. Thanks to enhanced nuclear recoil energies by diamond’s low mass carbon nuclei, and low energy threshold of cryogenic magnetic phonon sensors, the MAGNETO-χ detectors could offer high experimental sensitivity to sub-GeV dark matter scatterings. In addition, relatively fast timing resolution of the magnetic phonon sensor (~100 ns) despite their large sensing area, it offers strong phonon pulse shape discrimination (PSD) capability to separate out unwanted noise or non-nuclear recoil signals in the sub-keV region. This phonon PSD capability could be also useful for understanding the low energy excess problem that low threshold detector community is experiencing with. We present recent development progress of the MAGNETO-χ detectors including development of the magnetic phonon sensor, characterization of various diamond crystals for athermal phonon propagation, and the low energy response down to 60 eV in a context of the low energy EXCESS issue.
This work was performed under the auspices of the U.S. Department of Energy by Lawrence Livermore National Laboratory under Contract DE-AC52-07NA27344. This work was supported by the Laboratory Directed Research and Development program of Lawrence Livermore National Laboratory (22-FS-011) and DOE Office of Science HEP Advanced Detector R&D program.
The EDELWEISS collaboration searches for light Dark Matter (DM) particles using germanium detectors equipped with a charge and phonon signal readout. To circumvent the problem of the large background of events with no ionisation signal ("Heat-Only" events) that limit the sensitivity of our detectors equipped with Ge-NTD sensors, the collaboration has tested the use of NbSi Transition Edge Sensors (TES). The observed HO background reduction in a 200g detector equipped with a TES readout and operated underground in the Laboratoire Souterrain de Modane (LSM) has yielded a sensivity to DM masses down to 32 MeV/c² and cross sections down to 10$^-{29}$ cm². Further improvements have been more recently obtained by exploting the phonon yield from the Neganov-Luke-Trofimov effect to better resolve electron recoils from HO events. These results pave the way for a new detector design, named CRYOSEL, that is being optimized for such a discrimination.
The recent development of highly sensitive solid-state detectors has made it possible to search for light WIMP-like particles with only a few eV of deposited energy. Skipper CCDs allow us to resolve single-electron events, bringing the energy threshold down to 1.2 eV. In addition, some dark matter models predict a diurnal modulation in the DM particle flux. For certain parameters, this modulation is enhanced in the southern hemisphere due to the fact that the DM wind comes from 40 degrees north. The DMSQUARE experiment aims to probe this region of the parameter space using a Skipper CCD detector in Bariloche, southern Argentina. This experiment, using a 100 mg prototype detector, has already improved the previous limits for such models, obtained with a surface detector, by taking advantage of the modulation search. Recently, DMSQUARE has acquired data with a 2 g prototype detector, which is being moved to a shallow underground site (Sierra Grande mine, 1000 mwe). Data from the new detector will be presented.
In recent years, high sensitivity, low-threshold detectors employing transition edge sensor (TES) read out technology have garnered significant interest in the field of rare-event physics. Numerous experiments have incorporated these detectors for direct dark matter searches, Coherent elastic neutrino-nucleus scattering (CEvNS) studies and beyond. As these experiments scale up and operate larger arrays, a key challenge is to enhance the reproducibility among detectors while promoting modularity in terms of both the choice of absorber and sensor.
COSINUS (Cryogenic Observatory for SIgnals seen in Next-generation Underground Searches) has experimentally demonstrated that a novel cryogenic detector scheme, known as remoTES, can address these challenges. This innovative design can streamline the mass fabrication of reliable and reproducible detectors for the next generation of low-mass, rare-event physics searches. This contribution will present results from the latest prototypes, highlighting ongoing optimization efforts across various absorbers and configurations.
Cryogenic Rare Event Search with Superconducting Thermometers (CRESST) is a direct detection dark matter (DM) search experiment located at the Laboratori Nazionali del Gran Sasso in Italy. The experiment employs cryogenic and scintillating crystals to search for nuclear recoils from DM particles, and has achieved repeatedly threshold below 100 eV in a wide range of target materials including CaWO$_4$, LiAlO$_2$, Al$_2$O$_3$, and Si. However, at these energies, the ability to discriminate between potential DM signals and electromagnetic background is poor. Moreover, a significant challenge faced by all low-mass dark matter searches, including CRESST, is the existence of unknown event populations at very low energies known as the low energy excesses (LEEs). Therefore, having a reliable background model is of utmost importance.
To understand various background components in the measured spectra by CRESST, a detailed GEANT4-based model was developed and is continuously adapted to CRESST's current inventory of detector modules. I will present CRESST's background model and the related GEANT4-based simulation code "ImpCRESST''. The background model aims to include a wider range of radiopurity measurements for the materials used in the experiment in its future iteration.
In summary, this contribution provides a short overview of the experiment, a detailed status of the background model simulations, and the progress made towards measuring radiopurity in the screening campaign.
The Cryogenic Rare Event Search with Superconducting Thermometers (CRESST) is a highly sensitive Dark Matter experiment situated at the Laboratori Nazionali del Gran Sasso (LNGS) in Italy, with the capability to detect nuclear recoils down to 10 eV, making it one of the top experiments for probing the sub-GeV mass-parameter space.
However, distinguishing between Dark Matter recoils and beta-particles/gamma-rays at such low energies is hardly possible. Therefore, it is essential to understand the composition of radioactive background in the experimental reference data. This information can be utilised in an analysis to search for Dark Matter signals and enhance future detector modules, e.g. by improving the radiopurity of used materials.
Recently, the electromagnetic background model for CRESST-II has been significantly improved, and an extension to newer CRESST-III detector modules was made. The improvements include various simulated radiogenic and cosmogenic sources of radioactivity, the incorporation of more material screening results, a comprehensive description of the new detector modules, and a likelihood fit of the simulated spectral templates to the measured data.
This contribution will present enhanced background models of the detector module TUM40, as well as first background models of the Lise and the Detector A module.
The presence of a non-baryonic Dark Matter (DM) component in the Universe is inferred from the observation of its gravitational interaction. If Dark Matter interacts weakly with the Standard Model (SM) it could be produced at the LHC. The ATLAS Collaboration has developed a broad search program for DM candidates in final states with large missing transverse momentum produced in association with other SM particles (light and heavy quarks, photons, Z and H bosons, as well as additional heavy scalar particles) and searches where the Higgs boson provides a portal to Dark Matter, leading to invisible Higgs decays. The results of recent searches on 13 TeV pp data from the LHC, their interplay and interpretation will be presented.
Searches in CMS for dark matter in final states with invisible particles recoiling against visible states are presented. Various topologies and kinematic variables are explored, including jet substructure as a means of tagging heavy bosons. In this talk, we focus on the recent results obtained using the full Run-II dataset collected at the LHC.
The NA62 experiment at CERN took data in 2016–2018 with the main goal of measuring the $K^+ \rightarrow \pi^+ \nu \bar\nu$ decay. The NA62 dataset is also exploited to search for light feebly interacting particles produced in kaon decays. Searches for $K^+\rightarrow e^+ N$, $K^+ \rightarrow \mu^+ N$ and $K^+ \rightarrow \mu^+ \nu X$ decays, where N and X are massive invisible particles, are performed by NA62. The N particle is assumed to be a heavy neutral lepton, and the results are expressed as upper limits of $O(10^{-8})$ of the neutrino mixing parameter $|U_{\mu 4}|^2$. The X particle is considered a scalar or vector hidden sector mediator decaying to an invisible final state. Upper limits of the decay branching fraction for X masses in the range 10–370 MeV/c$^2$ are reported. An improved upper limit of $1.0 \times 10^{-6}$ is established at 90$\%$ CL on the $K^+ \rightarrow \mu^+ \nu \nu \nu$ branching fraction.
The NA62 experiment can be run as a "beam-dump experiment" by removing the Kaon production target and moving the upstream collimators into a "closed" position. More than $10^{17}$ protons on target have been collected in this way during a week-long data-taking campaign by the NA62 experiment. We report on the search for visible decays of exotic mediators from data taken in "beam-dump" mode, with a particular emphasis on Dark Photon and Axion-like particle Models.
New physics may have gone unseen so far at the LHC due to it being hidden in a dark sector. This may result in a rich phenomenology which we can access through portal interactions. In this talk, we present recent results from dark-sector searches in CMS using the full Run-2 data-set of the LHC. The analyses are based on proton-proton collision data corresponding to an integrated luminosity of up to 138 fb−1 taken at a center-of-mass energy of 13 TeV by the CMS experiment at the LHC.
Collider searches for dark matter (DM) so far have mostly focused on scenarios where DM particles are produced in association with heavy standard model (SM) particles or jets. However, no deviations from SM predictions have been observed. Several recent phenomenology papers have proposed models that explore the possibility of accessing the strongly coupled dark sector, giving rise to unusual and unexplored collider topologies. The results of recent searches on dark QCD, semi-visible jets, dark sector, dark photon, LLP, and ALPs on 13 TeV pp data from the LHC, their interplay and interpretation will be presented.
The Belle II experiment at the SuperKEKB asymmetric-energy electron-positron collider has been collecting the world’s highest-intensity collisions at the $\Upsilon$(4S) since 2019. A data set comparable in size to that of predecessor experiments, and collected with the new detector, enables unique or world-leading results. Examples include indirect searches for non-standard-model physics in the weak interactions of quarks, determinations of fundamental standard-model parameters, and direct searches for low-mass dark matter. This talk presents a selection of recent results and briefly discusses future perspectives.
The Galactic Center Excess (GCE) in GeV gamma rays has been debated for over a decade, with the possibility that it might be due to dark matter annihilation or undetected point sources such as millisecond pulsars. We investigate how the gamma-ray emission model used in Galactic center analyses affects the interpretation of the GCE's nature in terms of these two competing hypotheses using a set of gamma-ray emission models with increasing complexity. When different models lead to different conclusions, a general gap between the model space and reality may influence our findings. In this talk, we report the results of our study, showing that convolutional DeepEnsemble Networks can robustly detect the background components and the GCE in all gamma-ray emission model iterations. In addition, the predicted emission associated with the background components is consistent with the outcome of a traditional likelihood analysis. However, the reconstructed composition of the GCE is model-dependent. It is likely biased by the presence of a reality gap. We assess the severity of such a gap for each model instance using the One-Class Deep Support Vector Data Description method, and we show that it persists across all iterations. Our study casts doubt on the validity of previous conclusions regarding the GCE and dark matter and underscores the urgent need to account for the reality gap and consider previously overlooked ''out of domain''-uncertainties in future interpretations.
We investigate the characteristics of the gamma-ray signal following the decay of MeV-scale Axion-Like Particles (ALPs) coupled to photons which are produced in a Supernova (SN) explosion. This analysis is the first to include the production of heavier ALPs through the photon coalescence process, enlarging the mass range of ALPs that could be observed in this way and giving a stronger bound from the observation of SN 1987A. Furthermore, we present a new analytical method for calculating the predicted gamma-ray signal from ALP decays. With this method we can rigorously prove the validity of an approximation that has been used in some of the previous literature, which we show here to be valid only if all gamma rays arrive under extremely small observation angles (i.e. very close to the line of sight to the SN). However, it also shows where the approximation is not valid, and offers an efficient alternative to calculate the ALP-induced gamma-ray flux in a general setting when the observation angles are not guaranteed to be small. We also estimate the sensitivity of the Fermi Large Area Telescope (Fermi-LAT) to this gamma-ray signal from a future nearby SN and the possibility of reconstructing ALP properties in the case of a detection is discussed.
The High Altitude Water Cherenkov (HAWC) Observatory has been observing the Northern TeV gamma-ray sky since 2014. With a duty cycle of nearly 24 hours per day and a field-of-view of ~2 sr, it is an excellent instrument for performing unbiased surveys. Here, we present science results from the first eight years of operations. This includes the first catalog of astrophysical sources emitting above 100 TeV, the discovery of a new class of Galactic sources (TeV halos), the detection of several TeV gamma-ray binaries, and searches for dark matter. HAWC observes several dark matter-rich regions, such as dwarf galaxies, each day, allowing us to search for gamma rays from dark matter interactions in those targets. We will also discuss the status of HAWC’s multi-messenger and multi-wavelength programs, which include searches for GRBs, follow-ups to gravitational wave detections, and joint analyses with other TeV instruments.
The High Altitude Water Cherenkov (HAWC) observatory is highly suitable for large-scale survey work. The high duty time (95+%), large FoV (2 sr), and sensitivity from 300 GeV to above 100 TeV make it ideal for creating a catalog of very high energy (VHE) sources. Over the lifetime of the HAWC observatory, 4 catalogs have been produced 3 of which were constructed using the full HAWC energy range while another used a restricted (>56 TeV) range. This talk will focus on the status of the planned 4HWC (full energy range) catalog including the newly developed Multi-Source Fit algorithm inspired by the Fermi Extended Source search method. Using over 1000 additional days of data, improved event reconstruction algorithms using HAWC's fifth pass through data, and the improved search algorithm we expect a major improvement in the sensitivity and accuracy. The previous (3HWC) catalog found 65 sources above 5 sigma and I anticipate the 4HWC search will result in over 100 significant sources. In addition, the new search is more suited to fitting extended sources and disentangling complex regions. The 3HWC catalog found that 56 of 65 sources were associated with pulsars so it will be of interest to observe how this may change. In addition to a discussion surrounding the creation of the 4HWC catalog, I will present a preliminary look at the results of the new catalog search method in several regions of interest in HAWC maps such as the Crab Nebula, Cygnus Cocoon, and near the Geminga pulsar.
The instrumentation for gamma-ray astronomy has advanced tremendously during the last two decades. The study of the most violent environments in the Universe has opened a new window to understand the frontier of physics, exploring processes that are beyond the capabilities of Earth-based laboratories to replicate. One of the instruments at the forefront of gamma-ray astronomy is the MAGIC stereoscopic system, which consists of two 17-m diameter mirror dish telescopes located at 2200m a.s.l. on the Canary Island of La Palma, in Spain. The year 2023 marks the 20th anniversary of MAGIC, reaching the milestone of 200 publications in peer-reviewed journals over a wide range of research areas, covering astrophysics with Galactic and extragalactic objects, dark matter searches, and cosmology. MAGIC has established itself as a world-wide leading instrument for gamma-ray astronomy in the energy range from 20 GeV to beyond 100 TeV. MAGIC is an active participant in multiple multiwavelength and multimessenger observational campaigns, contributing to our understanding of the universe. In the conference, I will provide a status report of MAGIC, including the discussion of a few outstanding results during the last two decades and the prospects for the near future.
CUPID-Mo was a demonstrator for CUPID, a next generation neutrinoless double beta decay experiment. It consisted of an array of 20 enriched Lithium Molybdate cryogenic calorimeters equipped with 20 Germanium light detectors for particle identification. As well as providing an important demonstration of the detector technology, CUPID-Mo has achieved a series of world leading physics results. The discrimination of $\alpha$ from $\beta$/$\gamma$ particles enabled CUPID-Mo to reach the lowest ever background index for a bolometric 0$\nu\beta\beta$ decay experiment. This resulted in a world leading limit on 0$\nu\beta\beta$ decay in $^{100}$Mo. We will also present the results of a topological analysis of double beta decays to $^{100}$Ru excited states, with a measurement of the 2$\nu\beta\beta$ decay to 1st 0$^+$ excited states and new world leading limits on other processes. The very high signal to background ratio of 2$\nu\beta\beta$ decay to the ground state enables a range of further physics studies. We will present the most precise measurement of the 2$\nu\beta\beta$ decay to the ground state in any isotope, and studies of new physics beyond the Standard Model which could distort the spectral shape of the 2$\nu\beta\beta$ spectrum: 0$\nu\beta\beta$ with Majoron emission, 2$\nu\beta\beta$ decay with emission of Bosonic neutrinos and Lorentz invariance violation.
The Cryogenic Underground Observatory for Rare Events (CUORE) is the first bolometric experiment searching for 0νββ decay that has successfully reached the one-tonne mass scale. The detector, located at the LNGS in Italy, consists of an array of 988 TeO$_2$ crystals arranged in a compact cylindrical structure of 19 towers. CUORE began its first physics data run in 2017 at a base temperature of about 10 mK and has been collecting data continuously since 2019, reaching a TeO$_2$ exposure of 2 tonne-year in spring 2023. This is the largest amount of data ever acquired with a solid state cryogenic detector, which allows for further improvement in the CUORE sensitivity to 0νββ decay in $^{130}$Te. In this talk, we will present the new CUORE data release, based on the full available statistics and on new, significant enhancements of the data processing chain and high-level analysis.
SNO+ is a large multi-purpose liquid scintillator based experiment, with the main physics goal of searching for the neutrinoless double-beta decay of $^{130}$Te. Additional physics topics include the measurement of solar neutrinos, antineutrinos from reactors and the Earth, supernova neutrinos and the search for other rare events.
Since April 2022, the experiment is taking data with liquid scintillator and a 2.2 g/L PPO concentration, allowing the study of all radioactive backgrounds prior to the tellurium loading. In a first phase, 3900 kg of natural tellurium (0.5% loading) will be added to the scintillator for a predicted sensitivity of about 2$\times 10^{26}$ years (90% C.L.) with 3 years of livetime. Higher tellurium loading will follow for predicted sensitivities above $10^{27}$ years (3% loading).
In this talk I will focus on the current status of the experiment, its major radioactive backgrounds, and the prospects for the neutrinoless double-beta decay search.
N$\nu$DEx (No neutrino Double-beta-decay Experiment) is a new Se-based TPC detector that will be placed in China Jinping Underground Laboratory (CJPL) looking for neutrinoless double beta decay. NvDEx-100, the experiment phase with 100 kg of SeF6 gas, is currently being built and planned to be completed with installation at CJPL around the year 2025. I will present the current status of the experiments and the perspectives for future developments.
SeF$_6$ has very high electronegativity; for this reason, the electrons will recombine very quickly and the particles traveling toward the readout plane will be negative ions. A new kind of sensor, Topmetal-S, has been developed: it will allow us to read out the drifted charge and reconstruct the energy of the event with great precision even without physical amplification like electron avalanche.
The main advantages offered by N$\nu$DEx are two: firstly, the large rock overburden would decrease significantly the cosmogenic muon background. Second, the high Q-value of $^{82}\textrm{Se}$ (~3 MeV) will place the Region Of Interest above the energy range of the large majority of the environmental gamma's, allowing us to achieve an incredibly low-background environment, which ensures excellent perspectives for scalability.
ZICOS is a future experiment for neutrinoless double beta decay using $^{96}$Zr nuclei. In order to achieve sensitivity over $10^{27}$ years, ZICOS will use tons of $^{96}$Zr, and need to remove $^{208}$Tl backgrounds as observed by KamLAND-Zen one order of magnitude. For this purpose, we have developed new technique to distinguish the signal and background using topology of Cherenkov light. We have already measured this topology using HUNI-ZICOS detector, and the results clearly indicated the topology as effective even 1MeV electron. We have also developed the pulse shape discrimination for the extraction of PMT which receives Cherenkov lights in the liquid scintillator. In order to confirm above technique, we demonstrated beta-gamma events such as $^{208}$Tl beta decay scheme using $^{60}$Co source with UNI-ZICOS detector.
Here we will report some results obtained by recent measurement using UNI-ZICOS, and will also explain a plan to observe the two neutrino double beta decay for $^{96}$Zr nuclei using new detector 2nu-ZICOS.
The ability to detect liquid argon (LAr) scintillation light from within a densely-packed high-purity germanium detector array allowed the GERDA experiment to reach an exceptionally low background rate in the search for neutrinoless double-beta decay of $^{76}$Ge. Proper modeling of light propagation throughout the experimental setup, from any origin in the LAr volume to its eventual detection by the light read-out system, provides insight into the rejection capability and is a necessary ingredient to obtain robust background predictions. In this contribution, I will present a model of the GERDA LAr veto, as obtained by Monte Carlo simulations and constrained by calibration data, and highlight its application for background decomposition. The model is crucial to boost the sensitivity of beyond-the-standard-model double-beta decay signal searches, whose results have been recently published by GERDA. The LEGEND collaboration is further developing this modeling technique, applied to its LAr instrumentation system, to enable sensitive new-physics analyses with the LEGEND-200 detector and inform the LEGEND-1000 design.
he MicroBooNE experiment employs an 85-ton active volume liquid argon time projection chamber to detect neutrinos from both the on-axis Booster Neutrino Beam (BNB) and off-axis Neutrinos at the Main Injector (NuMI) beam. The objective of this investigation is to identify short baseline neutrino oscillations in a 3+1 sterile neutrino model and compare our results to previous anomalies found in experiments such as LSND, Neutrino-4, and gallium anomalies.
To achieve our goal, we utilize high-performance charged current electron neutrino and muon neutrino selections, as well as a powerful electron/photon discrimination. In this presentation, we will detail our results on this sterile neutrino search from MicroBooNE using the BNB beam. Additionally, we will examine the impact of a degeneracy resulting from the cancellation of electron neutrino appearance and disappearance, and demonstrate that combining data from the BNB and NuMI beams, which have substantially different electron to muon neutrino ratios, can break this degeneracy.
The ICARUS collaboration has employed the 760-ton T600 detector in a successful three-year physics run at the underground LNGS laboratory, performing a sensitive search for LSND-like anomalous $\nu_e$ appearance in the CNGS beam, contributing to the constraints on the allowed neutrino oscillation parameters to a narrow region around 1 eV$^2$. After a significant overhaul at CERN, the T600 detector has been installed at Fermilab. Following the cryogenic commissioning, in 2020 ICARUS started its operation collecting the first neutrino events from the Booster Neutrino Beam (BNB) and the Neutrinos at the Main Injector (NuMI) beam off-axis, which were used to test the ICARUS event selection, reconstruction and analysis algorithms. ICARUS completed its commissioning phase in June 2022, moving then to data taking for neutrino oscillation physics, aiming at first to either confirm or refute the claim by Neutrino-4 short-baseline reactor experiment. ICARUS will also perform measurements of neutrino cross sections with the NuMI beam and several Beyond Standard Model searches. After the first year of operations, ICARUS will jointly search for evidence of sterile neutrinos with the Short-Baseline Near Detector (SBND), within the Short-Baseline Neutrino (SBN) program. In this presentation, preliminary technical results from the data with the BNB and NuMI beams are presented both in terms of performance of all ICARUS subsystems and its capability to select and reconstruct neutrino events.
The Deep Underground Neutrino Experiment (DUNE) is a next generation long-baseline neutrino oscillation experiment designed to observe neutrino and antineutrino oscillation patterns to precisely measure neutrino mixing parameters. DUNE near detectors will measure and constrain the neutrino flux and constrain the response for a near-far detector oscillation measurement. The 2x2 Demonstrator is a demonstrator for the DUNE ND-LAr near detector based on the ArgonCube design. The 2x2 Demonstrator will characterize neutrino-Argon interactions in the few-GeV regime. Composed of a 2x2 grid of four optically segmented LArTPC modules sandwiched between upstream and downstream repurposed MINERvA tracking planes, each TPC module has a footprint of 0.7 m by 0.7 m and is 1.4 m tall. The 2.6 metric ton LAr active mass is instrumented by 337k charge-sensitive pixels at 4 mm pitch and thin-profile scintillation traps for 25% optical coverage. The detector will acquire neutrino data in Fall 2023 in the NuMI beamline at Fermilab. Roughly 70k charged-current and 30k neutral-current active volume fiducialized neutrino vertex interactions are expected per week in NuMI medium energy RHC operation. In addition to copious GeV-scale neutrino interactions, physics data at the MeV-scale is possible, leveraging the near 100% uptime free-streaming, few hundred keV charge readout pixel trigger thresholds. A system design overview and commissioning status will be reported in the presentation.
The Deep Underground Neutrino Experiment (DUNE) far detectors require readout of several hundred thousand charge-sensing channels immersed in the largest liquid argon time projection chambers ever built, calling for cryogenic front-end electronics in order to be able to adequately instrument the full detector. These electronics must satisfy power constraints of < 50 mW per channel to minimize the thermal load on the cryogenic system, be designed with lifetimes of 20+ years to remain functional throughout the expected lifetime of DUNE, and be able to reliably communicate with warm interface electronics on the other side of cold cables that are up to 30 meters long. The upcoming ProtoDUNE-II program at the CERN neutrino platform will consist of 2 liquid argon time projection chambers, which will serve as demonstrators of the technologies that will be used in the first 2 DUNE far detectors, including the final design of the cryogenic charge readout electronics. This design consists of a chain of 3 different ASICs designed for operation in liquid argon: LArASIC for analog charge amplification, ColdADC for digitization into 14-bit signals, and COLDATA for multiplexing, serialization, and digital control. This talk will discuss the design of these electronics, preliminary performance results from the ProtoDUNE-II assembly experience, and plans for the ProtoDUNE-II runs.
The SBND experiment is a liquid argon time projection chamber (LArTPC), which serves as the near detector to the Short Baseline Neutrino (SBN) program at Fermilab. With only 110 m between the detector volume and the beam target, SBND will record over a million of neutrino interactions per year, more than any LAr experiment to date. Furthermore, the detector is located on the surface and exposed to cosmic rays. As a result, a sophisticated and reliable trigger system is needed to ensure high efficiency of neutrino data while maintaining data rates which are manageable in downstream analysis. This talk will detail how the SBND trigger system achieves both of these goals.
The Jiangmen Underground Neutrino Observatory (JUNO) is a 20 kton liquid scintillator detector currently under construction in Southern China. Beyond its main purpose of determining the neutrino mass ordering, JUNO will contribute to the search for the SUSY-favored proton decay into a kaon and an antineutrino. To reach the estimated sensitivity for p $\rightarrow$ K$^+$+ $\bar{\nu}$ of $9.6 \times 10^{33}$ years at 90 % C.L. after 10 years of data taking, event selection relies strongly on the signal structure of the daughter kaon and differentiation from atmospheric neutrino backgrounds.
This poster presents the influence of the kaon’s light emission behavior on the proton decay event selection efficiency as well as first test of an experiment characterizing the particle’s energy dependent light output.
The Yemilab, a new deep underground laboratory, has been constructed to be located under the Yemi mountain at the Jeongseon in Korea. The overburden is 1,000 m from the top of the Yemi mountain which may provide 5 times better muon mitigation than Y2L, and the laboratory area is approximately 3,000 m^2 which is 10 times larger than Y2L. We can access the laboratory using a cage that has 4 m/s vertical speed through the 600 m shaft and electric vehicles as transportation through the 800 m tunnel. The electricity, mobile networks, and facility for safety have been prepared for operation since the end of 2022.
Two major physics programs, AMoRE-II to search for a neutrinoless double beta decay of 100Mo and COSINE to search for a WIMP as a strong candidate of dark matter, are preparing to start the initial operation at the end of 2023. To provide a low radioactive background environment for those experiments, the radioactivity of the rock, radon level, muon rates, and neutron flux are measuring and monitored since the initial operation.
We report on the construction of the Yemilab, the current status of the facility for the scientific programs, and discuss future applications.
The Sanford Underground Research Facility (SURF) has been operating for more than 15 years as an international facility dedicated to advancing compelling multidisciplinary underground scientific research in rare-process physics, as well as offering research opportunities in other disciplines. SURF laboratory facilities include a Surface Campus as well as campuses at the 4850-foot level (1500 m, 4300 m.w.e.) that host a range of significant physics experiments, including the LUX-ZEPLIN (LZ) dark matter experiment and the MAJORANA DEMONSTRATOR neutrinoless double-beta decay experiment. The CASPAR nuclear astrophysics accelerator completed the first phase of operation and is planning for the second phase beginning in 2024. SURF is also home to the Long-Baseline Neutrino Facility (LBNF) that will host the international Deep Underground Neutrino Experiment (DUNE). SURF offers world-class service, including an ultra-low background environment, low-background assay capabilities, and electroformed copper is produced at the facility. SURF is preparing to increase underground laboratory space. Plans are advancing for construction of new, large caverns (nominally 100m L x 20m W x 24m H) on the 4850L (1500 m, 4200 mwe) on the timeframe of next-generation experiments (~2030). SURF plans to leverage existing advisory and community committees as well as engage the underground science community to inform plans for future laboratory space.
The Laboratoire Souterrain de Modane is the deepest tunnel-access underground laboratory in Europe. The experimental site is protected by a 4800 mwe overburden that reduce the muon flux to 5 muons/m2/day, and is thus ideal for a wide range of applications requiring ultra-low radioactivity levels. We will present the evolution of this facility and of its science program in the domain of Dark Matter, neutrinoless double-beta decay and multi-disciplinary sciences.
In the 3+1 neutrino scheme with an additional state, we consider the thermalisation of neutrinos in the early Universe in the so-called very low reheating scenarios. This process could be incomplete due to the lack of interactions, leading to a reduced contribution of neutrinos to the cosmological energy density of radiation. We calculate this contribution, usually measured in terms of the parameter $N_{\rm eff}$, taking into account the full $4\times 4$ neutrino mixing matrix. We find the corresponding bounds from cosmological data on the $3+1$ neutrino scenario (neutrino squared mass differences and mixings) as a function of the reheating temperature $T_{\rm RH}$.
We discuss thermal leptogenesis in the framework of the flipped SU(5) unification model, where the Majorana masses of neutrinos are generated through Witten's two-loop mechanism.
Our analysis shows that this model is compatible with the current experimental constraints on both the neutrino sector and observed baryon asymmetry. Moreover, it indicates an upper (and lower) limit on the absolute light neutrino mass scale and constrains the possible proton decay branching ratios.
We study the phenomenological properties of the three-loop radiative seesaw model proposed by Krauss, Nasri, and Trodden. In this model, the tininess of the neutrino masses and there is a dark matter candidate. We show constraints on the parameter space of this model by mainly considering the DM relic density, the lepton flavour violation constraints, and neutrino oscillation data.
We also discuss the possibility of baryogenesis via leptogenesis.
This presentation is mainly based on Phys. Rev. D 105, 095018 (2022) and 2211.10059.
The sexaquark, a hypothesized six-quark bound state, has garnered interest as a potential dark matter candidate. At the same time, there are many arguments in the literature that place severe limitations on this possibility. Assuming it exists and is stable, I will advance a compelling case for the limited viability of the sexaquark as a dark matter candidate by presenting the first calculation of its scattering electromagnetic cross section with Standard Model particles and by investigating its freeze-out abundance. The leading-order term in the electromagnetic cross section is due to the sexaquark's polarizability, which we obtained using lattice QCD. I will show that this implies a direct detection cross section that would be visible for a stable sexaquark constituting even a tiny fraction of the dark matter. I will also explore the expected sexaquark abundance derived from the freeze-out of its interactions in the early universe, and explore the detectability of such a thermally produced sexaquark component.
The wealth of theoretical and phenomenological information about Quantum Chromodynamics (QCD) at short and long distances collected so far in major collider measurements has profound implications in cosmology. We provide a brief discussion on the significant implications of the strongly coupled dynamics of quarks and gluons and the effects due to their collective motion on the physics of the early universe and in astrophysics. In particular, we speculate on the relationship between the existence of quasi-classical saturated QCD matter and the production of primordial black holes.
Contribution is based in part on the review article A. Addazi et al.: Cosmology from Strong Interactions, Universe 8 (2022) 9, 451, e-Print: 2204.02950 [hep-ph]
In this seminar, I will explore the potential for uncovering new neutrino physics through the use of dark matter direct detection experiments and its complementarity with spallation source experiments. In particular, I will analyse the Sterile Baryonic Neutrino Model, an extension of the SM in which we add a sterile massive neutrino. I will show how the sterile neutrino can be generated through the inelastic scattering of an active neutrino with the target material of the experiments in both direct detection and spallation source experiments, giving rise to a characteristic spectrum. This might allow for a reconstruction of the neutrino mass (in the event of a positive detection), which is limited by the experiment energy threshold and resolution. Direct detection experiments, being sensitive to the solar tau neutrino flux, add extra complementary information that allows to improve the determination of the sterile neutrino couplings and its mass.
In 2021, the MAJORANA DEMONSTRATOR experiment ended its search for neutrinoless double beta decay $^{76}$Ge. Shown to be one of the world-leading ultra-low-background facilities we modified the experiment to search for one of the rarest isotope decays. The isotope $^{180m}$Ta is the only known isotope in nature that occurs in an isomeric state instead of the ground state. The isomeric decay is spin-suppressed, and its decay has never been observed. Beyond understanding the mechanisms that play a role in its decay, the rare state can be exploited to search for dark matter (DM) through a stimulated decay. In this project, we installed clean Ta samples between the Ge detectors, and exploit the ultra-low background underground environment, the high resolution of the MAJORANA detectors, and the well-established analysis routines to search for the nuclear decay and the possible induced emission by DM. In this talk I will present the results from the first year of data taking, and its implications to the dark sector.
This material is supported by the U.S. Department of Energy, Office of Science, Office of Nuclear Physics, the Particle Astrophysics and Nuclear Physics Programs of the National Science Foundation, and the Sanford Underground Research Facility. We acknowledge the support of the U.S. Department of Energy through the LANL/LDRD Program.
In the ECHo experiment large arrays of low temperature metallic magnetic calorimeters enclosing $^{163}$Ho are used for the high resolution measurement of the electron capture spectrum. The goal of the experiment is to achieve the sensitivity to detect an extremely small spectral shape distortion in the end point region due to an effective electron neutrino mass smaller than 1 eV/c$^2$.
The first ECHo-1k phase was designed to test the properties and reproducibility of detectors enclosing $^{163}$Ho. In a proof-of-principle experiment, we acquired about 10$^8$ $^{163}$Ho events allowing to reach a sensitivity below 20 eV/c$^2$. For this and, in particular, to achieve sub-eV sensitivity in future stages of ECHo, systematic uncertainties have to be identified and reduced. We discuss the progress in the understanding the $^{163}$Ho electron capture spectrum, including the newly determined $Q$-value, and in the description of background. We present methods we have developed for the analysis of data acquired in ECHo-1k and the results we have obtained so far.
At the same time, preparation of large detector arrays and multiplexed readout for the ECHo-100k phase is progressing. Important milestones related to $^{163}$Ho implantation in MMC arrays on wafer scale and multiplexing have been reached. We present the status of ECHo-100k and discuss our perspectives for achieving a sensitivity at the 1 eV/c$^2$ level for the effective electron neutrino mass in the coming phase.
CaWO$_4$ and Al$_2$O$_3$ are well-known target materials for cryogenic detectors deployed in experiments searching for rare events like coherent elastic neutrino-nucleus scattering (CE$\nu$NS) with NUCLEUS or hypothetical dark matter-nucleus scattering with CRESST. With detection thresholds in the sub-keV range, these experiments need verified and reliable simulations of background components at such energies, which are challenging for general purpose simulation codes like Geant4.
The ELOISE project aims to assess the reliability of Geant4 simulations of electromagnetic (EM) processes in CaWO$_4$ and Al$_2$O$_3$ at sub-keV energies and, if needed, to improve it. Currently, we are studying the agreement of dedicated Electron Energy Loss Spectroscopy (EELS) of CaWO$_4$ and Al$_2$O$_3$ samples, which were provided by TU Munich, with Geant4 simulations. We simulate the energy loss with each relevant EM physics implementation provided by Geant4 and assess its compatibility with the EELS measurements.
In this contribution, I will motivate the challenge of sub-keV simulations and outline the scope of ELOISE. Afterwards I will introduce the EELS reference data set and discuss the observed spectral features. Subsequently, I will report the simulations of ionisation energy loss in CaWO$_4$ and Al$_2$O$_3$ based on Geant4’s unmodified EM physics implementation. Finally, I will give a preliminary assessment of the compatibility between Geant4 simulation and measured reference data.
The main objective of the Scintillating Bubble Chamber (SBC) collaboration is to detect 1-10GeV dark matter by combining the electron recoil suppression of conventional bubble chambers with the scintillation properties of liquid noble elements. The use of noble elements provides two benefits. First, the potential to reduce the energy threshold to 100eV by efficiently converting most of the energy deposited by electron recoils to light to suppress bubble creation. Second, the ability to collect event-by-event energy information from the scintillation. To test this technology, SBC is building its first prototype at Fermilab. This prototype includes the scintillation system using liquid argon doped on the order of 100 ppm of Xe as the scintillator, and the light collection devices are 32 Hamamatsu VUV4 silicon photomultipliers (SiPMs). This talk serves as an exposition of the progress being made on SBC and testing of the scintillation system done at Queen's University.
We investigate a novel way of probing light dark matter boosted by supernova neutrinos incorporating the time-of-flight (TOF) information. The DM mass mχ < O(10 MeV) can be boosted to relativistic speed and surpasses the detector energy threshold, eg. Super-K/Hyper-K/DUNE. The additional TOF manifests the direct mχ measurement and is irrelevant to the DM-ν cross section σχν. The application of TOF to background suppression provides much improved sensitivities. In this talk, we will also show the resulting constraint from SN1987a and projected sensitivity from the next GC SN on DM-ν and DM-e cross sections with a broad range of mχ. The results are improved by 1-3 order of magnitudes comparing to the existing bounds. Prospects of exploiting TOF information in other astrophysical systems to probe exotic physics with other DM candidates are discussed.
The DARWIN collaboration is currently designing a detector for high-mass WIMP dark matter with sensitivity to the neutrino fog. The project has the support, in the framework of the new XLZD consortium, of the XENONnT and the LZ collaborations, who are operating the currently most sensitive detectors of this type. With a planned target mass of 40 tonnes of liquid xenon (LXe), the DARWIN detector will probe the remaining accessible parameter space for high-mass WIMPs, and will also be sensitive to solar and supernova neutrinos. A target mass goal of 60 tonnes LXe, which will be the new design baseline if DARWIN becomes realised within XLZD, would further increase the sensitivity. This presentation focuses on the WIMP sensitivity, and on the R&D projects ongoing to make this detector a reality.
DarkSide run since mid-2015 a 50-kg-active-mass dual-phase argon Time Projection Chamber (TPC), filled with low radioactivity argon from an underground source and produced world-class results for both the low mass ($M_{WIMP}< 20 GeV/c^2$) and high mass ($M_{WIMP} > 100 GeV/c^2$) direct detection search for dark matter.
The next stage of the DarkSide program will be a new generation experiment involving a global collaboration from all the current argon based experiments. DarkSide-20k is designed as a 20-tonne fiducial mass dual-phase Liquid Argon TPC with SiPM based cryogenic photosensors and is expected to be free of any instrumental background for exposure of 200 tonne x year. Like its predecessor, DarkSide-20k will be housed at the INFN Gran Sasso underground laboratory (LNGS), and it is expected to attain a WIMP-nucleon cross-section exclusion sensitivity of $7.4\times 10^{-48}\, cm^2$ for a WIMP mass of $1 TeV/c^2$ in a 200 t yr exposure. DarkSide-20k will be installed inside a membrane cryostat containing more than 700 t of liquid Argon and use a Gd-PMMA based neutron veto detector. This talk will give the latest updates on the DarkSide-20k project.
Darkside-20k is a global direct dark matter search experiment situated underground at LNGS (Italy), designed to reach a total exposure of 200 tonne-years free from instrumental backgrounds. The core of the detector is a dual phase Time Projection Chamber (TPC) filled with 50 tonnes of low-radioactivity liquid argon.
The entire TPC wall is surrounded by a gadolinium-loaded polymethylmethacrylate, which acts as a neutron veto, immersed in a second low-radioactivity liquid argon bath enclosed in a stainless steel vessel. The neutron veto is equipped with large area Silicon Photomultiplier (SiPM) array detectors, placed on the TPC wall. SiPMs are arranged in a compact design meant to minimize the material used for Printed Circuit Board (PCB), cables and connectors: Veto PhotoDetection Units (vPDUs).
A vPDU comprises 16 Tiles, each containing 24 SIPMs, together with front end electronics, and a motherboard, which distributes voltage and control signals, sums tiles channels, and drives the electrical signal transmission. The neutron veto will be equipped with 120 vPDUs.
The talk will focus on the production of the first vPDUs, describing the assembly chain in the UK institutes, in order to underline the rigorous QA/QC procedures, up to the final characterization of the first completed prototypes. Tests have been extensively performed in liquid nitrogen baths either for the single Tiles and for the assembled vPDUs redacting a "quality passport" for each component.
DarkSide-50 is a direct detection experiment hunting for dark matter utilizing a dual-phase argon time projection chamber at LNGS in Italy.
On the basis of the ionization spectrum alone, it has established the most restrictive exclusion limit for low-mass dark matter candidates.
Due to its peculiar behavior, it is possible to search for dark matter in a model-independent manner by exploiting the expected variation of the relative velocity between dark matter and Earth.
We describe the first search for such an event rate modulation with argon using the DarkSide-50 ionization signal in this presentation, in particular a Lomb–Scargle analysis was used to look for a 1 year period peaking at June 2nd.
As a result of years of stable operation of the detector and a thorough knowledge of the detector's response, we were able to obtain the lowest energy threshold ever attained in this kind of experiments, on the order of sub-keV.
Dark matter candidates with masses below 10 GeV/c² hold promise, and a new detector, DarkSide-LowMass, is proposed based on the DarkSide-50 detector and the progress towards the DarkSide-20k. DarkSide-LowMass is optimized for low-threshold electron-counting measurements, and sensitivity to light dark matter is explored for various potential energy thresholds and background rates. Our studies show that DarkSide-LowMass can achieve sensitivity to light dark matter down to the level of the solar neutrino fog for GeV-scale masses and significant sensitivity down to 10 MeV/c², taking into account the Migdal effect or interactions with electrons. Requirements for optimizing the detector's sensitivity are explored, as well as potential gains from modeling and mitigating spurious electron backgrounds that may dominate the signal at the lowest energies.
A major global effort is currently underway to obtain underground argon for DarkSide-20k (DS-20k), the first large-scale detector of the Global Argon Dark Matter Collaboration (GADMC). Assessing the purity of the underground argon in terms of Ar-39 is crucial for the physics program of this experiment. To achieve this goal, the GADMC is building the DArTinArDM experiment at the LSC laboratory in Spain.
The radiopure DArT chamber (~1 liter), containing underground argon, will be placed in the center of the ~1 ton atmospheric argon ArDM detector, serving as an active veto for gamma radiation from the detector materials and surrounding rock. DArTinArDM is designed to measure the Ar-39 depletion factor in the underground argon with a sensitivity better than 1 mBq/kg, ensuring the radiopurity level of the different underground argon batches necessary for DS-20k.
The DArT chamber is currently operating underground at Laboratorio Subterráneo de Canfranc (LSC) in a test cryostat, with the purpose of setting protocols for hardware and software operations, optimizing the operating conditions of the setup and developing analysis tools.
In parallel, the ArDM detector is being refurbished with a new passive shield and a new light detection system to improve its performances in minimizing and rejecting background events.
In this talk, I will provide an overview of the status and prospects of the DArTinArDM project.
The Recoil Directionality project (ReD) within the Global Argon Dark Matter Collaboration aims to characterize the response of a liquid argon (LAr) dual-phase Time Projection Chamber (TPC) to neutron-induced nuclear recoils and to measure the charge yield for low-energy recoils. The charge yield is a critical parameter for the experiments searching for dark matter in the form of low-mass WIMPs and measurements in Ar below 10 keV are scarce in the literature. This project will cover the gap down to 2 keV.
The TPC is irradiated by neutrons produced by an intense $^{252}$Cf fission source in order to produce Ar recoils in the energy range of interest. The energy of the nuclear recoils produced within the TPC by (n,n') scattering is determined by detecting the outgoing neutrons by a dedicated neutron spectrometer made of 18 plastic scintillators. The kinetic energy of neutrons interacting in the TPC is evaluated event-by-event by measuring the time of flight between a BaF$_2$ detector located close to the $^{252}$Cf source, which tags the primary fission event by detecting the accompanying radiation, and the neutron spectrometer. Data with the $^{252}$Cf source are being taken during the Winter of 2023 at the INFN Sezione di Catania. The experiment will be complemented by calibrations with low-energy internal sources of $^{83m}$Kr and $^{37}$Ar diffused inside the TPC.
In this contribution, we describe the experimental setup and the preliminary results from data analysis.
Sub-GeV dark matter (DM) has been gaining significant interest in recent years, since it can account for the thermal relic abundance while evading nuclear recoil direct detection constraints. Such light DM must carry a larger energy to be probed, either directly or through missing energy/momentum, making beam dump and fixed target experiments ideal for this mass range. Here, we extend the previous literature, which mainly focuses on the predicted experimental signals of scalar and fermionic DM, by considering simplified DM models in which the Standard Model is extended by one vector DM candidate along with one spin-1 mediator. In this analysis, we identify the parameters consistent with the observed relic abundance, calculate the relevant constraints from existing experiments and measurements, and predict the sensitivity of future experiments such as the upcoming LDMX. We find that spin-1 DM is testable by future experiments, and for certain spin-1 models, will be the first DM models probed by LDMX.
The constituents of dark matter are still unknown, and the viable possibilities span a very large mass range. Specific scenarios for the origin of dark matter sharpen the focus on a narrower range of masses: the natural scenario where dark matter originates from thermal contact with familiar matter in the early Universe requires the DM mass to lie within about an MeV to 100 TeV. Considerable experimental attention has been given to exploring Weakly Interacting Massive Particles in the upper end of this range (few GeV – ~TeV), while the region ~MeV to ~GeV is largely unexplored. It is therefore a priority to explore. If there is an interaction between light DM and ordinary matter, as there must be in the case of a thermal origin, then there necessarily is a production mechanism in accelerator-based experiments. The most sensitive way, (if the interaction is not electron-phobic) to search for this production is to use a primary electron beam to produce DM in fixed-target collisions. The Light Dark Matter eXperiment (LDMX) is a planned electron-beam fixed-target missing-momentum experiment that has unique sensitivity to light DM in the sub-GeV range. This contribution will give an overview of the theoretical motivation, the main experimental challenges and how they are addressed, as well as projected sensitivities in comparison to other experiments.
$U(1)_{L_\mu - L_\tau} \equiv U(1)_X$ model is anomaly free within the Standard Model (SM) fermion content, and can accommodate the muon (g−2) data for $M_{Z′}∼O(10−100)$ MeV and $g_X ∼(4−8)×10^{−4}$. WIMP type thermal dark matter (DM) can be also introduced for $M_{Z′}∼2M_{DM}$, if DM pair annihilations into the SM particles occur only through the s-channel Z′ exchange. In this work, we show that this tight correlation between $M_{Z′}$ and $M_{DM}$ can be completely evaded both for scalar and fermionic DM, if we include the contributions from dark Higgs boson (H1). Dark Higgs boson plays a crucial role in DM phenomenology, not only for generation of dark photon mass, but also opening new channels for DM pair annihilations into the final states involving dark Higgs boson, such as dark Higgs pair as well as $Z′Z′$ through dark Higgs exchange in the s-channel, and co-annihilation into $Z′H_1$ in case of inelastic DM. Thus dark Higgs boson will dissect the strong correlation $M_{Z′}∼2M_{DM}$, and much wider mass range is allowed for $U(1)_X$-charged complex scalar and Dirac fermion DM, still explaining the muon $(g−2)$. We consider both generic $U(1)_X$ breaking as well as $U(1)_X→Z_2$ (and also into $Z_3$ only for scalar DM case).
Referece : https://arxiv.org/abs/2204.04889
Any Light Particle Search II (ALPS II) is a dual optical cavity enhanced light-shining-through-a-wall (LSW) experiment at DESY in Hamburg looking for axions and axion-like particles with a target search sensitivity of $g_{a \gamma \gamma}$ down to $2 \times 10^{-11}\,\textrm{GeV}^{-1}$ for masses $m_a \leq 0.1\,\textrm{meV}$. Two 120$\,$m long strings of superconducting dipole magnets have been set up, each providing a magnetic field-length product of $560\,\textrm{T}\cdot\textrm{m}$. A resonant optical cavity with a record-worthy storage time of as high as 6.75$\,$ms has been constructed to encompass one magnet string. During its initial data-taking phase ALPS~II will be operated with a simplified optical configuration that facilitates the characterization of the experiment. The first science run will presumably take place in the second quarter of 2023 and delve into uncharted parameter space by few orders of magnitude in comparison to previous LSW experiments. In this talk we will describe the current status of ALPS II, present presumably the first results, and draw the perspectives for further improvements in its search sensitivity.
As it was reported at ICRC 2021 [1], TAUP 2021 [2], and VCI 2022 [3], subterrestrial neutron spectra show weak but consistent anomalies at multiplicities ~100 and above. The origin of the excess events remains ambiguous, but, in principle, it could be a signature of Dark Matter WIMP annihilation-like interaction with a massive Pb target. However, since the results of the available measurements are below the 5-sigma discovery level, and the observed anomalous structures are on a significant muon-induced background, an independent verification at even greater depth is needed. For that purpose, we have launched NEMESIS 1.4 – a new dedicated experiment consisting of 1134 kg of Pb and 14 He-3 detectors with PE moderators and a fully digital readout. NEMESIS 1.4 has been taking data at the deepest level (1.4 km, 4000 m.w.e.) of the Pyhäsalmi mine, Finland, since November 2022. The presentation will describe the idea behind the new setup, compare the first results with Monte Carlo simulations and other available data, and give the outlook for further research. If the existence of the anomalies is unambiguously confirmed and the model interpretation [4] positively verified, this will be the first Indirect Detection of Dark Matter in the laboratory.
[1] https://doi.org/10.22323/1.395.0514
[2] http://doi.org/10.1088/1742-6596/2156/1/012029
[3] https://doi.org/10.1016/j.nima.2022.167223
[4] TAUP abstract #221
Candidates for dark matter are proposed and searched from the sub meV to TeV scales. The indirect observations don’t provide sufficient power to constrain to a narrow parameter space of the searches. One of the dark matter candidates, a deeply bound (uuddss) sexaquark, $S$, with mass in the GeV range is hypothesized to be long lived and very compact, described within the Standard Model of Particle Physics without extensions. $S$ properties make it particularly challenging to explore experimentally.
In this contribution we will show an experimental scheme [1] in which $S$ could be produced at rest through the formation of helium-3 antiprotonic atoms and their subsequent annihilation into S +K$^+$K$^+$+$\pi^-$. This channel is particularly clean as there is no other channel naturally populating the same final state. It can be uniquely identified both through the background-free tag of a S=+2, Q=+1 final state, as well as through full kinematic reconstruction of the final state recoiling against it.
[1] M. Doser, G. Farrar, G. Kornakov, “Searching for a dark matter particle with anti-protonic atoms”, arXiv:2302.00759 [hep-ph]
The Cherenkov Telescope Array (CTA) is the next generation TeV gamma-ray observatory and the first prototype of the Large Sized Telescope (LST-1) was built in La Palma, Spain and is in its commissioning phase. Since one of the current generation TeV telescopes, MAGIC, is operating in the same site, it is possible to observe the same gamma-ray events with both instruments and perform joint stereoscopic analysis with both higher collection area and stronger background rejection. Therefore we routinely perform joint observations. We report the newly developed analysis pipeline for analysis of such joint data and its performance based on both the Monte Carlo simulations and data collected from the Crab Nebula. We find the joint observations allows us to detect 30% weaker sources compared to MAGIC-alone analysis and 40% compared to LST-1-alone analysis.
The search for axion-like particles (ALPs) is a hot topic in physics since axions were proposed as a solution for the strong CP problem. The axion mass and coupling to standard model particles extend over a wide range and can be constrained by collider experiments as well as by astrophysical and cosmological observations.
ALPs are candidates for dark matter particles, making their search even more exciting. The MAGIC telescopes, operating in the very-high-energy gamma-ray range, search for dark matter in several astrophysical environments and in this work we present the results of ALPs searches in the Perseus Galaxy clusters and the constraints we obtained.
When propagating through magnetic fields, very high-energy gamma rays can convert to ALPs, leaving signatures in the observed spectral energy distribution. We have analysed ~ 40 hours of data from the the MAGIC observations of the Perseus Cluster, in particular, the radio galaxy NGC1275 and the BL Lac object IC310. Given its proximity and strong magnetic field, which extends up to several hundreds of kpc, Perseus is a perfect candidate for the search of ALPs. By searching for distinctive spectral signatures and using a new statistical approach to the analysis, we confirmed constraints on ALPs with masses in the neV-μeV range and established the most stringent limits for ALPs with masses around 40 neV. Our results open the road for performing similar studies using the new generation of gamma-ray ground-based instruments.
The Extragalactic Background Light (EBL) is the accumulated light produced throughout the history of the universe, spanning the UV, optical, and IR spectral ranges and mostly originating from stars, directly or re-processed by dust. However, measuring the EBL total intensity (beyond the contribution of resolved discrete sources) is challenging due to its faintness compared to foreground diffuse light like zodiacal light. A possible technique exploit the Very High Energy (VHE) photons coming from sources at cosmological distances. VHE photons can interact with the EBL and produce electron-positron pairs, an absorption process that can be identified in the observed gamma-ray spectrum. This method requires assumptions on the intrinsic spectrum of the source, which can affect the robustness of EBL constraints. In this contribution, through the use of Monte Carlo simulations, and of archival data of the MAGIC telescopes, we have studied the impact that the assumptions so far adopted in the literature have in the estimates of the EBL density, and how the use of more generic ones would modify the results. These studies can impact our understanding of evolution of Universe, gamma-ray propagation and large-scale structure formation.
The intergalactic magnetic field (IGMF) is the weak magnetic field present in the voids of large-scale structures in the Universe. The interdisciplinary studies on the IGMF link several research fields of cosmology, astrophysics and astroparticle physics.
Recently, gamma-ray observations in the GeV-TeV domain have been used to probe the possible presence and main properties of IGMF using different techniques. Gamma-Ray Bursts (GRBs) have been proposed as interesting targets for the detection of a secondary delayed pair echo emission, a signature of the presence of a non-zero IGMF. This delayed signal depends on the configuration of the IGMF and can be used to constrain its properties.
In this contribution, we present a phenomenological study of IGMF signatures from GRBs with TeV gamma-ray detectors. We predict the pair echo emission component generated by GRBs based on the intrinsic properties of GRB190114C and we determine the most convenient observational strategy for the current and future generation of gamma-ray instruments exploring different IGMF strengths, observational times and source intrinsic properties.
Blazars are one of the prime objects to be studied in the current multi-messenger era. However, even though they have been studied for decades, the underlying emission mechanisms are far from understood. In 2022, IXPE announced the first detection of X-ray polarization in blazars, which opened a new window for probing acceleration and radiation processes.
In this contribution, we put the first IXPE observations of the two blazars Mrk 501 and Mrk 421 in a multiwavelength context, including data from the radio regime up to the very-high-energy (>0.2 TeV, VHE) γ-rays. We investigate the X-ray polarization evolution, and compare it, for the first time, with the behavior in the VHE band. For Mrk 501, we find clear evidence for an extreme emission state in March 2022 with a synchrotron component peaking above 1 keV. Additional NuSTAR data allows us to accurately characterize the component and evaluate the underlying electron population. While the X-ray emission is harder and brighter than usual, the VHE data reveals a far lower inverse-Compton dominance than usual. Mrk 421 shows a variety of emission states during 2022, which allows to investigate multi-band correlations around the IXPE observations. For one IXPE night, significant flux variations are seen on an hourly time scale in the hard X-rays by NuSTAR, which we use to access information about the acceleration and cooling processes in the source exploiting hysteresis patterns.
Some candidates for the theory of quantum gravity allow for Lorentz invariance violation (LIV). If Lorentz's invariance is violated, it may cause an observable effect on the light curve and spectra of very high energy (VHE, E > 100 GeV) photons coming from cosmic sources. One of the possible consequences of the LIV is in-vacuo dispersion which implies that the photon group velocity is energy dependent. In this line of LIV studies, one needs a fast variable source and the highest possible photon energies. So, in order to explore the possibility of a LIV effect, we analysed an exceptional VHE flare from the blazar Mrk 421 detected by the MAGIC telescopes in April 2014. The flare reached energies up to 10 TeV with fast intra-night variability. Through an innovative time-binned likelihood analysis, which has never been used in LIV studies before, we searched for arrival-time delays that increase linearly or quadratically with the photon energy. We were unable to significantly detect any energy-dependent time delay, which enabled us to establish stringent limits on the expected energy scale for LIV.
The absolute mass of neutrinos is one of the most important riddles yet to be solved, since it has many implications in Particle Physics and Cosmology. HOLMES is an ERC project started in 2014 that will tackle this topic. It will perform a model independent calorimetric measurement of the neutrino mass with a sensitivity of the order of 1 eV using 1000 low temperature microcalorimeters detectors (TES) embedded with 163Ho.
After an intensive measurement campaign, the detector fabrication procedure was performed successfully and their response without 163Ho was exhaustively characterized, alongside the capability of readout 32 detectors at the same time with the microwave multiplexing technique.
The custom ion implanter has also undergone extensive testing, and is now ready to perform an implantation at low dose (around 1 Hz per channel) in the TESs for the very first time. These achievements have represented an essential milestone for HOLMES.
In the last quarter of 2023, we’re supposed to be taking data from 64 detectors and we should be in an early stage of the analysis. Nevertheless, this low activity phase of the experiment will lead to the most stringent limit (O(10) eV) on the neutrino mass with a calorimetric technique.
In this contribution, I will present the recent experimental results achieved by the collaboration.
The LEGEND Collaboration pursues an experimental program to search for the neutrinoless double-beta $(0\nu\beta\beta)$ decay of $^{76}Ge$ with discovery potential at half-lives beyond $T_{1/2} (0\nu\beta\beta) = 10^{28}$ yr. The first phase, LEGEND-200 has started operations at LNGS with 140 kg of HPGe detectors and plans to install additional detectors in the near future. With an exposure of 1 ton-year and a background index in the region of interest of less than $2 \cdot 10^{-4}$ cts/(keV kg yr), LEGEND-200 will reach a sensitivity of $T_{1/2} (0\nu\beta\beta)$ of about $10^{27}$ years.
In this talk, we present the experimental setup of LEGEND-200, the installation and commissioning of the first 140 kg of enriched detectors, and the performance of the sub-detector systems. We discuss the energy resolution, stability, and performance of the pulse shape discrimination of the HPGe detectors, the photo-electron yield and suppression factors of the liquid argon instrumentation, and the efficiency of the water Cherenkov detector.
This work is supported by the German MPG, BMBF, and DFG; the Italian INFN; the Polish NCN and MNiSW; the Czech MEYS; the Slovak SRDA; the European ERC and Horizon programs; the Swiss SNF; the UK STFC; the U.S. DOE and the NSF, the LANL, ORNL and LBNL LDRD programs; the Russian RFBR; the Canadian NSERC and CFI; the LNGS and SURF facilities.
The LEGEND Collaboration pursues an experimental program to search for the neutrinoless double-beta $(0\nu\beta\beta)$ decay of $^{76}Ge$ with discovery potential at half-lives beyond $T_{1/2} (0\nu\beta\beta) = 10^{28}$ yr. The first phase, LEGEND-200 has started operations at LNGS with 140 kg of HPGe detectors and plans to install additional detectors in the near future. With an exposure of 1 ton-year and a background index in the region of interest of less than $2 \cdot 10^{-4}$ cts/(keV kg yr), LEGEND-200 will reach a sensitivity of $T_{1/2} (0\nu\beta\beta)$ of about $10^{27}$ years.
In this talk we present initial results based on the first months of data-taking with LEGEND-200. We will discuss the event selection, the analysis and characterization of signal and background event topologies leading to the signal acceptance and the background rejection efficiencies. We will also review our assessment of the background index and the resulting measured final-state energy spectrum, except for the blinded signal region.
This work is supported by the German MPG, BMBF, and DFG; the Italian INFN; the Polish NCN and MNiSW; the Czech MEYS; the Slovak SRDA; the European ERC and Horizon programs; the Swiss SNF; the UK STFC; the U.S. DOE and the NSF, the LANL, ORNL and LBNL LDRD programs; the Russian RFBR; the Canadian NSERC and CFI; the LNGS and SURF facilities.
The Cryogenic Underground Observatory for Rare Events (CUORE) is a tonne scale detector searching for neutrinoless double beta decay ($0\nu\beta\beta$) in $^{130}$Te. The CUORE detector is made of 988 TeO$_{2}$ crystals operated at around 15 mK in the Gran Sasso National Laboratories (Italy).
Being the $0\nu\beta\beta$ a very rare process, every single background component has to be precisely understood. Material screenings and assays, together with a detailed set of Monte Carlo simulations, accomplish this essential and complex task, modeling the experimental background. This is essential to better understand the data of CUORE and to deepen the knowledge about the cryogenic setup, which is planned to be used also for the next generation experiment: CUPID.
The CUORE background model reconstructs the data by means of a Bayesian fitting algorithm.
We will present the new results of this analysis showing an estimation of all the contamination activities of crystals and surrounding materials. In particular, a dedicated delayed coincidence analysis allows to better determine surface $\alpha$ contaminations which represent the most prominent background in the $0\nu\beta\beta$ region of interest.
We will also present the updated measurement of the $2\nu\beta\beta$ decay half-life of $^{130}$Te.
The main stage of AMoRE, AMoRE-II, is about to start its data taking. The experiment takes place 1000 meters underground at Yemilab in Jeongseon, Korea. A cryogenic system containing molybdenum-100 enriched crystal detector modules is surrounded by heavy passive shields and muon counters made of plastic scintillator panels and water Cherenkov detectors. We expect the background level to be below $10^{-4}$ count/keV/kg/year with a 10 keV full-width-half-maximum energy resolution at the region of interest. Starting with 90 detector modules consisting of about 29 kg of lithium-molybdate crystals, the detector will eventually be upgraded using 180 kg of crystals. Data-taking will last for more than five years. The projected sensitivity covers the half-life of neutrinoless double beta decay of molybdenum-100 up to about $4.5\times 10^{26}$ years, corresponding to the effective Majorana mass of 18 — 31 meV.
Imaging sensors made from an ionization target layer of amorphous selenium (aSe) coupled to a silicon complementary metal-oxide-semiconductor (CMOS) active pixel array for charge readout are a promising technology for neutrino physics. The high spatial resolution in a solid-state target provides unparalleled rejection of backgrounds from natural radioactivity in the search for neutrinoless $\beta\beta$ decay and for solar neutrino spectroscopy with $^{82}$Se. We present results from the first aSe/CMOS devices optimized for charge collection in aSe. We explore the scientific reach of a large neutrino detector with the proposed technology based on our experimental understanding of the detector performance.
Project 8 is a next-generation experiment aiming to directly measure the neutrino mass using the tritium endpoint method with a targeted sensitivity of 40 meV. Having established a new measuring technique, Cyclotron Radiation Emission Spectroscopy (CRES), the next development phase will demonstrate CRES on a large source volume, culminating in a pilot-scale CRES experiment with atomic tritium. A promising option is a mode-filtered, cylindrical resonant cavity in which cyclotron radiation from magnetically trapped beta electrons couples only to the lowest eigenmode, maximizing effective volume and minimizing signal complexity. I will show
recent progress in the experimental design, including a small scale cavity CRES proof-of-concept apparatus to demonstrate CRES in cavities and its scalability to large volumes.
This work is supported by the US DOE Office of Nuclear Physics, the US NSF, the PRISMA+ Cluster of Excellence at the University of Mainz, and internal investments at all institutions.
Currently-running and planned neutrinoless double beta decay ($0\nu$-DBD) experiments aim to reach an experimental sensitivity in terms of half-life at the order of 10$^{27}$–10$^{28}$ yr to probe the inverted neutrino hierarchy using a short list of isotopes – $^{76}$Ge, $^{100}$Mo, $^{130}$Te and $^{136}$Xe. However, $^{96}$Zr is also a promising nuclide due to its high energy transition (Q$_{2\beta}$ = 3.35 MeV) that helps to overcome the issue with the environmental gamma-radioactivity (up to 2.6 MeV) and internal beta-active nuclides from U/Th decay chains (up to 3.27 MeV). The high transition energy is also favorable from a theoretical point of view, as the expected half-life for $0\nu$-DBD is proportional to (Q$_{2\beta}$)$^{5}$.
Here we present the first complex study of Cs$_2$ZrCl$_6$ (CZC) scintillating crystals in terms of their chemical- and radio-purity, scintillating performance and pulse-shape discrimination ability. The low-background measurements with two CZC crystals (11 g and 24 g) over 456.5 days, supported their high radiopurity leading to a counting rate of 0.17 (kg$\cdot$keV$\cdot$yr)$^{-1}$ at the Q$_{2\beta}$ of $^{96}$Zr. Limits on different DBD modes of $^{96}$Zr were set at the level T$_{1/2}$ $\sim$ 10$^{17}$-10$^{20}$ yr (90$\%$ C.L.). The detailed analysis of the internal background components was performed to be used in further developments of Cs$_2$ZrCl$_6$ detectors and to optimize the future experiment.
The observation of coherent elastic neutrino nucleus scattering (CEvNS) has opened the window to many physics opportunities. In this talk I will discuss the implication of the observation of CEvNS by the COHERENT Collaboration using two different targets, CsI and argon, on new physics scenarios. These include, for instance, new light mediators.
The NUCLEUS experiment aims to detect and characterize coherent elastic neutrino nucleus scattering (CEvNS) in an ultra-low background environment using a 10 g cryogenic detector made of CaWO4 and Al2O3 crystals. The experiment will be installed between the two 4.25 GW reactor cores of the Chooz-B nuclear power plant in the French Ardennes, with commissioning scheduled for 2023 at the Technical University of Munich before moving to the Chooz reactor site in 2024. NUCLEUS will provide important insights into neutrino physics and potential new physics beyond the Standard Model.
Low-threshold detectors for coherent elastic neutrino-nucleus scattering (CEvNS) and light dark matter (DM) searches rely crucially on understanding their response to sub-keV nuclear recoils, which is difficult to access using conventional calibration techniques. The CRAB collaboration proposed a new method based on mono-energetic nuclear recoils in the 100 eV - 1 keV range induced by the emission of MeV-$\gamma$ rays following thermal neutron capture. We performed simulation studies on the expected energy spectrum which include in detail the involved nuclear physics for typical detector materials, e.g., Si, Ge, CaWO$_4$, and Al$_2$O$_3$. Recently, we reported a major breakthrough with the first direct observation of a nuclear recoil peak at the 100 eV scale measured with a NUCLEUS CaWO$_4$ detector.
Currently, the CRAB collaboration prepares precision measurements with a clean thermal neutron beam at a research reactor at TU Wien. The sensitivity of the CRAB method is further increased by the detection of the emitted $\gamma$-ray in coincidence with the subsequent nuclear recoil and by the interplay of the timing of the γ-cascade and the nuclear recoil. With its novel idea, CRAB provides a direct and accurate calibration of nuclear recoils and will enable future quenching factor measurements in the region of interest of light DM and CEvNS experiments. This is essential for finding and studying new physics. The latest results and the experimental strategy will be presented.
The CONUS experiment aimed to detect coherent elastic neutrino-nucleus scattering (CEνNS) of reactor antineutrinos on germanium nuclei in the fully coherent regime. It operated from 2017 to 2022 at 17m from the 3.9 GWth core of the Brokdorf nuclear power plant (Germany). The CEνNS search was performed with four 1 kg point-contact high-purity germanium (HPGe) detectors, which provided a sub keV energy threshold with background rates in the order of 10 events per kg, day and keV.
The analysis of the final CONUS data set allows to establish the current best limit on CEνNS from a nuclear reactor with a germanium target, improving by an order of magnitude on the previous world's best limit. Moreover, this new result refutes other measurements where quenching factors deviating significantly from Lindhard theory were considered. The results from the last physics run together with the quenching measurements performed by CONUS will be discussed in this talk.
The Coherent Neutrino-Nucleus Interaction Experiment (CONNIE) is located at a distance of 30 m from the core of the Angra 2 nuclear reactor in Rio de Janeiro, Brazil. Its goal is to detect the coherent elastic scattering of reactor antineutrinos, known as CEvNS, off silicon nuclei using fully depleted high-resistivity charge-coupled devices (CCDs). Running since 2016, the experiment has set upper limits on the CEvNS rate and placed stringent constraints on some scenarios beyond the Standard Model involving light mediators. Recently, the collaboration has also explored the experiment's sensitivity to other exotic scenarios such as milli-charged particles. With the purpose of further reducing the energy threshold, two Skipper CCDs were installed in the summer of 2021. The collaboration has demonstrated stable operation of the new sensors with a readout noise of 0.15 electrons and a single-electron rate of ~0.05 e-/pix/day. New techniques have been developed to reduce the effects of instrumental backgrounds, allowing to reach a threshold of 20 eV. In this presentation, I will discuss the performance of Skipper CCDs, along with the enhanced data selection techniques employed. Additionally, I will present the preliminary results of the reactor ON-OFF low energy spectrum difference from the Skipper data. Finally, I will touch upon the future prospects for detecting CEvNS with Skipper-CCDs technology.
The low-energy coherent neutrino nucleus elastic scattering ($\nu A_{\rm{el}}$) is being studied in a number of experimental programs around the world. As part of TEXONO's neutrino research program at Kuo-Sheng nuclear power plant, state-of-art high purity point-contact Germanium detectors with $\mathcal{O}$(100 eV) threshold are utilized to study such low-energy neutrino interactions at the complete coherency regime. This presentation will provide an overview of current $\nu A_{\rm{el}}$ activities and recent results at the TEXONO experiment. We will also discuss the quantitative studies of quantum-mechanical coherency effects in $\nu A_{\rm{el}}$.
Taking advantage of recent NaI crystal detector development, we established stable data-taking of the NEON experiment with a 16.7 kg crystal array at 23.7 meters away from the reactor core of the Hanbit nuclear power plant (2.8-GWth) in April 2022. NEON aims at detecting a coherent neutrino-nucleus scattering process for reactor antineutrinos.
Using preliminary analyses of approximately 150 (143) days of reactor-ON(OFF) data, we found that the detector performs stably and better than expected, reaching crystal light yield of the unprecedented 24 photoelectrons per 1 keV energy deposit. Until now, 6 counts/day/kg/keV of the single-hit background rate at 0.6 keV have been achieved. The status of the experiment and its expected sensitivity assuming 0.2 keV energy threshold depending on quenching systematics will be reported.
The observation of neutral-current coherent elastic neutrino-nucleus scattering (CEvNS) at the COHERENT experiment has opened a new window to search for new physics beyond the Standard model. In this talk we will focus on the sensitivity of current CEvNS data to neutrino electromagnetic properties, such as the neutrino charge radius or the neutrino magnetic moment. The discovery potential of upcoming CEvNS experiments will also be discussed.
In the past years there has been a growing interest in superconducting qubits. This technology, other than being one of the most promising ones for the realization of quantum computers, has also applications for particle detectors. Detectors relying on superconducting qubits are already being used to search for light dark matter candidates such as hidden photons or axions.
As the technology will improve in the next years, quasiparticles, i.e. broken Cooper pairs, are expected to become the main limit to the performances of qubits. Previous researches have already shown that ionizing radiation is a source of quasiparticles, that can result in a loss of the qubit state or, if multiple qubits are involved, correlated errors. Radioactivity has also been found to affect the stability of magnetic flux biasing of fluxonium qubits. Investigating further these effects and developing mitigation strategies is then crucial for the development of next-generation quantum devices.
In our research we studied the behavior and the performances of a fluxonium qubit in the Laboratori Nazionali del Gran Sasso (LNGS) deep-underground facility. The facility is surrounded by 1.4 km of rock, which acts as a natural shield for cosmic rays, allowing the characterization of the qubit in an unprecedented low-radioactivity environment.
In this contribution we will present the results of these measurements and the comparison with what obtained in the above ground characterization of the same qubit.
Ionizing radiation has been shown to have deleterious effects on superconducting qubit performance, particularly by generating correlated errors in multiple qubits, which is particularly problematic for quantum error correction codes. To better study the effects of ionizing radiation on superconducting qubits and sensors, we have recently installed a dilution refrigerator in the Shallow Underground Laboratory (30 meters-water-equivalent overburden) at Pacific Northwest National Laboratory. The fridge will be augmented with a lead shield designed to reduce the interaction rate from external gammas by greater than 99%. We estimate the residual ionizing radiation interaction rate from the fridge itself and from typical instrumentation hardware. We have assayed the radioactive contaminant levels in samples of superconducting qubits, which were found to be very low in radioactivity, and in common coax connectors and circuit board composites, which we find to substantially dominate the radiation budget. An assessment of required steps to further reduce backgrounds is provided. I will also present some details on a recent publication describing the Geant4 Condensed Matter Physics (G4CMP) software, which simulates charge and phonon transport in crystal substrates and transduction into quasiparticle production in superconducting films.
JUNO is building a 20 kt liquid scintillator (LS) detector at a depth of 700 m underground, and the radioactive control of the environment is very important. The whole underground space at JUNO site is about 300,000 m3, including the main hall of 120,000 m3 and a number of attached halls and tunnels, making it the largest underground laboratory in the world. Since the laboratory is located underground, the rocks and water will release large amounts of 222Rn (radon) into the air. The detector components have the risk of air exposure during installation, so radon and its daughter nuclei can attach to the surface of the material and contaminate the LS. Therefore, the control of radon concentration in the experimental hall is very important. Moreover, the residual dust is another source of radioactive background. The cleanliness inside the experimental hall should reach the level of Class 100,000 or better. In order to achieve an installation environment with low radon and well cleanliness, the optimization of the ventilation was carried out in the experimental hall. The radon concentration in the experimental hall has been stabilized at about 100 Bq/m3 with great efforts. Both the radon and the cleanliness level have met the requirements. Details about the strategies of radon concentration and cleanliness control in underground environment at JUNO site will be reported in this talk.
This work summarize different approaches that were carried out in the Modane Underground Laboratory (LSM). In this work the simulation of Radon daughter implantation on different surfaces is presented. The work compares a Geant4 based approach to the SRIM code . This lies in the simulation of the nucllear recoil on a metal plate. The different materials are tested respectively to radon deposition. Mainly we try to simulate accurately the nuclear recoil and the different surface states that will govern the implantation depth. Moreover different material were tested in radon deposition chamber that allowed us to test different environmental possibilty. the main material and packing are tested and the accuracy of simulation is tested.In the conclusion a discussion is made to check if this simulation can be generalized to underground experiment and the surface lead 210 deposition background background contribution coming from the storage of materials before building the experiment.This work could be discuss as a possibility to anticipate the background coming by monitoring the radon level or giving a radon budget for the experiment building and anticipate the lead 210 contribution.
Many physics goals of future large LAr detectors like DUNE hinge on the achievement of high radiopurity to minimize backgrounds to low-energy signals like supernova and solar neutrinos. Radon in particular is a concerning source of backgrounds, as its progeny generate diffuse signals from betas, gammas, and neutrons at the MeV-scale. In this talk, we report a measured limit on the specific activity of Rn222 in the bulk LAr of the MicroBooNE neutrino detector at Fermilab during standard data-taking periods. This measurement, achieved with newly developed low-energy LArTPC reconstruction and analysis techniques, is the first of its kind for a noble element detector incorporating liquid-phase purification. We also demonstrate the calorimetric capabilities of single-phase LArTPC technology at the ~MeV and sub-MeV scale with reconstructed energy spectra of betas and alphas from tagged isotope decays.
Further details at
https://taup2023.hephy.at/social-events/
Further details at
https://taup2023.hephy.at/social-events/
Dark Matter constitutes more than 80% of the total amount of matter in the Universe: we know it exists, we can guess some of its properties, but we have no idea of what it actually is. This is humbling and it constitutes one of the most pressing issues in cosmology and particle physics today. Notoriously, the range of masses for possible candidates to the role of Dark Matter covers more than 80 orders of magnitude. Even limiting only to elementary particles, the range is huge: looking for an axion or a WIMP is like being an explorer and setting off to search for something that can have the size of an atom or of a continent.
We will review quickly the main ideas behind this huge variety and focus on some specific cases.
Dark matter accounts for 23% of the mass-energy density of the Universe, however, its nature and origins remain the most important open questions in physics. The search for Weakly Interacting Massive Particles (WIMPs), one of the leading dark matter particle candidates, is now in a decisive phase, with experiments targeting both the high-mass and the low-mass (<10 GeV) WIMP scenarios. This talk will present the status of the leading experimental searches and summarize constraints on main theoretical models. Searches of heavy non-WIMP dark matter candidates will be also be briefly summarized. Finally, perspectives and limitations for future dark matter searches with very large next generation noble liquid detectors will be discussed.
We review the motivation for the axion as a solution of the strong
CP puzzle and as a candidate for cold dark matter. Then we discuss
benchmark axion models and present their predictions concerning
(i) axion dark matter abundance and (2) axion couplings to the Standard Model.
Finally, we give an overview on the discovery potential of current and planned
axion experiments, reaching from axion dark matter direct detection,
over searches for solar axions, to direct production and detection
of axions in the laboratory.
The existence of dark matter, indicated by astronomical observations, is one of the main proofs of physics beyond the standard model. Despite its abundance, dark matter has not been directly observed yet. This talk reviews the latest results from accelerator-based experiments with a focus on recent highlights.
COSINUS (Cryogenic Observatory for SIgnals seen in Next generation Underground Searches) is designed to unveil the nature of the dark matter signal claim by the DAMA/LIBRA collaboration. COSINUS develops NaI cryogenic scintillating calorimeters with transition edge sensors (TESs) to test the detection of the annually modulating signal observed by DAMA/LIBRA independently from the target material and the dark matter model. With a dual channel detector measuring both the energy converted into phonons and into scintillation light from a particle interaction in the NaI crystal, COSINUS can discriminate event-by-event the electromagnetic background from the nuclear recoils. Applying the novel remoTES design to a 1 cm$^{3}$ NaI crystal, COSINUS reached a baseline resolution of 441 eV in the phonon channel. Optimisation studies to adapt this readout design to larger mass crystals (of up to 90 g) are ongoing. The construction of COSINUS in the National Laboratory of Gran Sasso in Italy started in autumn 2021, and since then progresses persistently. The next big milestone is the commissioning of the cryogenic apparatus, foreseen to be completed by the end of 2023. The data taking with a first detector array is planned to start in early 2024; first physics results are anticipated after about one year of data taking, in 2025.
The SABRE experiment aims to find Dark Matter through an annual modulation in the rate of ultra-high purity NaI(Tl) crystals in order to provide a model independent test of the signal observed by DAMA/LIBRA.
SABRE will be a double-site experiment, with two similar detectors located in the Northern hemisphere (LNGS, Italy) and in the Southern hemisphere (SUPL, Australia), in order to disentangle seasonal or site-related effects and verify the nature of any modulating signal.
SUPL is a newly built facility ready for the construction and commissioning of SABRE South this year. Using the already established LNGS facilities, a Proof-of-Principle was carried out from 2020 to 2022 to characterize the SABRE benchmark crystal NaI-33, demonstrating a background rate of 1.20±0.05 dru, the lowest ever reached after DAMA/LIBRA.
Two more crystals were grown recently and are currently under measurement in passive shielding underground at LNGS. Based on these promising results, and considering the limitations of using liquid scintillators at LNGS, SABRE North is proceeding to a full scale design with purely passive shielding made of copper and polyethylene.
Instead, SABRE South will have the crystal detectors immersed in a LAB based liquid scintillator veto, further surrounded by passive steel and polyethylene shielding and an additional plastic scintillator based muon veto on top.
This talk will report the status and prospects of SABRE, covering both the Northern and Southern facilities.
ANAIS is a direct dark matter detection experiment whose goal is to confirm or refute in a model independent way the positive annual modulation signal reported by DAMA/LIBRA. ANAIS-112, consisting of 112.5 kg of NaI(Tl) scintillators, is taking data at the Canfranc Underground Laboratory in Spain since August 2017. Results corresponding to the analysis of three years of data show no modulation and are incompatible with DAMA/LIBRA. However, testing this signal relies on the knowledge of the scintillation quenching factors (QF) for the conversion of nuclear recoil energy depositions with respect to the same energy deposited by electrons. Previous measurements of the QF in NaI(Tl) do not agree. Consequently, in order to fully understand the response of the ANAIS-112 detectors to nuclear recoils, a specific neutron calibration program is being developed. This program combines two different approaches: on the one hand, sodium QF measurements were carried out in a monoenergetic neutron beam; on the other hand, the study presented here aims at the evaluation of the QF by exposing directly the large ANAIS-112 crystals to neutrons from low activity 252Cf sources. Comparison between the onsite neutron calibrations and detailed GEANT4 simulations of the full experimental set-up allows testing different QF models. Some results will be discussed. In addition, preliminary efforts to include the non-linear light respone of NaI(Tl) in the simulations will be presented.
The Weakly Interacting Massive Particle (WIMP) is considered to be the hypothetical particle that has been the leading candidate for dark matter for decades. The PICOLON (Pure Inorganic Crystal Observatory for Low energy Neutr(al)ino) project is directly search for WIMP dark matter using ultra-pure NaI(Tl) crystals at the Kamioka underground Laboratory.
In the search for WIMP, the quenching factor (QF) of NaI(Tl) is required to determine the WIMP sensitivity. Here, QF is the scintillation light yield ratio of nuclear recoil and electron recoil at the same energy deposit. QF absolute value and its energy dependence in the low energy region (~100 keV) have been discrepant in previous studies. It is necessary to verify whether the discrepancy is due to the individual crystal differences or the effect of systematic errors.
To measure the QF, the NaI(Tl) scintillator developed at PICOLON was irradiated with 2.45 MeV monochromatic neutrons generated by a discharge-type compact D-D fusion neutron source at the Institute of Advanced Energy, at Kyoto University. The QFs of Na were obtained at six points in the range of 19 ~ 101 keV.
Understanding nuclear recoil quenching factors, the ratio of the scintillation light yield produced by nuclear and electron recoils of the same energy, is critical for rare event searches, such as dark matter and neutrino experiments. Because NaI(Tl) crystals are widely used for dark matter direct detection and neutrino-nucleus elastic scattering measurements, the low-energy quenching factor of the NaI(Tl) crystals is substantially important. The quenching factor for NaI(Tl) scintillating crystals has been measured by several experimental groups for energies above 5 keVnr for Sodium and 10 keVnr for Iodine. We have developed a NaI(Tl) detector with a high light yield of approximately 25 photoelectrons per keVee and an event-selection and analysis method based on waveform simulations that are specialized for studies of events with energies as low as a sub keVee region. As part of these efforts, we have measured quenching factors for nuclear recoil energies below 5 keVnr and 10 keVnr for Na and I, respectively. This talk will present the results and prospects for future quenching-factor measurements for NaI(Tl) crystals.
NaI-based experiments are becoming increasingly popular in the field of direct dark matter searches with the DAMA-LIBRA experiment being stand out for its reported observation which is in direct contrast with other results. Most of these experiments use TI-doped NaI crystals as single-channel scintillation-only detectors. In these types of experiments, a precise measurement of the quenching factor (QF) is crucial for accurately calibrating the energies of hypothetical WIMP-induced nuclear recoil signals and conclusively validating the DAMA/LIBRA results. However, QF values for NaI(TI) measured in various studies exhibit inconsistencies, and the impact of TI dopant concentration on the QF of NaI has not been systematically studied yet.
To address these discrepancies, a systematic study was conducted by COSINUS (Cryogenic Observatory for SIgnatures seen in Next-generation Underground Searches) in collaboration with TUNL (Triangle Universities Nuclear Laboratory). Five ultra-pure NaI crystals, each with different Tl dopant concentrations, were irradiated using a mono-energetic neutron beam to extract the QF values as a function of energy. This study aims to shed light on the QF mystery in the field and provide a better understanding of the discrepancies reported by various experiments, particularly in the low-energy range of 1-30 keV_nr. The latest results of our investigation will be presented in this presentation.
In this talk, I will discuss how the injection of electrons and positrons from dark matter (DM) annihilation or decay can generate magnetic turbulence in galaxies.
This effect sets a lower limit to the (self-)confinement of the electrons and positrons and thus to their expected radiative emission.
I will specifically apply this approach to the study of synchrotron radiation in dwarf spheroidal galaxies, showing bounds on WIMP DM obtained from radio observations of the Draco galaxy at the Giant Metre Radio Telescope.
Despite recent developments of sensitive dark matter detectors, the mass and nature of dark matter remain poorly constrained, and thus a broad observational strategy may prove helpful toward its ultimate identification. We have developed and tested a novel model-independent approach which utilizes the recent Breakthrough Listen public data release of three years of observation by the Green Bank Telescope. The method assumes only a quasi-monochromatic radio line from decay or annihilation of the dark matter, and additionally that the line exhibits a Doppler shift with position according to the solar motion through a static galactic halo. This approach has been tested and refined on a subset of L-band data; in this talk we will report results from the full L- and S-band data sets
A radiative decaying Big Bang relic with a mass $m_a≃5−25$ eV, which we dub ``blue axion'', can be probed with direct and indirect observations of the cosmic optical background (COB). The strongest bounds on blue-axion cold dark matter come from the Hubble Space Telescope (HST) measurements of COB anisotropies at 606 nm. We suggest that new HST measurements at higher frequencies (336 nm and 438 nm) can improve current constraints on the lifetime up to an order of magnitude, and we show that also thermally produced and hot relic blue axions can be competitively probed by COB anisotropies. We exclude the simple interpretation of the excess in the diffuse COB detected by Long Range Reconnaissance Imager (LORRI) as photons produced by a decaying hot relic. Finally, we comment on the reach of upcoming line intensity mapping experiments, that could detect blue axions with a lifetime as large as $10^{29}$ s or $10^{27}$ s for the cold dark matter and the hot relic case, respectively.
ISAI, Investigating Solar Axion by Iron-57, is an experiment dedicated for independent measurement of an axion-nucleus coupling constant $g_{aN}$ without introducing mixture of the other interactions. Iron-57, the third most abundant and stable iron isotope, would be in core of the Sun. Monochromatic 14.4 keV axion would be produced by de-exiction of the thermally excited isotope in the Sun and could be detected as an 14.4 keV $\gamma$ via the inverted production process of the isotope placed on the Earth. We developed the experimental setup which is composed of an event-triggered extreme low-background monolithic X-ray pixel detector surrounding the enriched iron-57 foil, passive shields for environmental radiations, position sensitive timing plastic counter to veto cosmic-ray, cryogenic chamber and the readout electronics. In this talk, I will present the experimental apparatus, the commissioning, the first observation, the prospect of sensitivity in current and near future and the upgrade.
Axions are intriguing candidates for dark matter. Depending on the formation mechanism of axion dark matter, the axion field may exhibit substantial density fluctuations on small scales. These density fluctuations lead to the formation of self-gravitating clumps of axions, known as miniclusters and axion stars. In this talk, I will discuss these clumps and what is, and what is not, known about them, and how to, perhaps, find them. In one of the classical axion dark matter scenarios (where the Peccei-Quinn symmetry is broken after the end of inflation), most of the axion dark matter may be bound in such axion clumps. On the one hand, this makes "direct detection" type searches for axions such as ADMX more difficult since the ambient axion density might be much lower than the usual ~0.3 GeV/cm3 expectation. On the other hand, such axion clumps might offer new exciting possibilities for "indirect detection" of axions: if such an axion clump would encounter a neutron star, the axions could resonantly convert into radiophotons in the neutron star's magnetosphere. The signal would be a narrow spectral line, strongly anisotropic, and lasting a typical time scale of ~1 year for an axion minicluster to ~1 minute for an axion star.
Primordial black holes (PBHs) as a dark matter (DM) candidate become popular again recently. Through their Hawking radiation, we can analysis their signal by $\gamma$-ray emissions. Our work focuses on cross-correlating the MeV $\gamma$-ray emissions and the cosmic microwave background shear to constrain the fraction of PBHs as DM. Near-future data can provide a tight constraint on the fraction of the Schwarzschild PBHs in the mass range around $10^{17}$g, like CMB-S4 project and the $\gamma$-ray telescope e-ASTROGAM. Some astrophysical sources also contributed to the observed emission in the MeV energy band. Furthermore, the constraining ability can be improved by another order of magnitude when taking the PBHs model with spins into account. This technology with proper coming data could importantly fill the gaps with PBHs fraction limits in the asteroid mass range.
The talk will present the status of the Virgo interferometer for the preparation of the fourth Observing Run (O4), started on May 25th. An overview of the hardware upgrades the detector has undergone in the past years and of the commissioning activities will be given, focusing on the instrument's performances in terms of sensitivity and duty cycle.
KAGRA is a gravitational wave detector located at Kamioka in Japan. KAGRA has two unique key features compared to the other ground-based gravitational wave detectors: One is constructed at the underground site and the other is utilizing cryogenic sapphire mirrors for the main mirrors. Underground site has a smaller seismic vibration, which is one of the dominant noise sources at low frequency region, than the surface of the ground. Utilizing cryogenic mirrors reduces thermal noise, which is one of fundamental noises of gravitational wave detectors.
KAGRA will start international joint observation with LIGO and Virgo from May 24, 2023 and have a commissioning break to improve the sensitivity. In this presentation, overview and up-to-date status of KAGRA will be reported.
In the present work it is presented a formulation of a new control strategy for the angular degrees of freedom of a Fabry-Perot cavity in the presence of radiation pressure effect for Advanced Virgo+ (AdV+) Phase II experiment. The main difference with Phase I configuration is the introduction of large terminal masses. The different physical dimensions of the two masses and the consequent different momenta of inertia introduce a not negligible asymmetry of the mechanical system which is translated in an impossibility of decoupling all the degrees of freedom. Given this difficulty, the possibility of designing SISO controllers (Single Input-Single Output) is left out. A new approach of designing MIMO controllers (Multi Input-Multi Output) in time-domain is investigated. Optimal Control Theory is used in order to design controllers which allow, by the minimization of a specific cost function, to obtain direct closed-loop stability with the optimal phase margin available. The present work will explain different topics: starting from the analytical description of the Fabry-Perot cavity, first (i) a State Space formulation of the mechanical system is obtained; then (ii) the design of a LQI control (Linear Quadratic Integral regulator) is described; to complete the control loop design architecture, (iii) the design of a state estimator, i.e. Kalman Filter, is reported, by using realistic data of sensors noise in order to evaluate robustness and convergence limitation of the filter.
Large-scale Cryogenic Gravitational-Wave Telescope, KAGRA, is a second-generation gravitational-wave detector (GWD) in Japan. The features distinguishing KAGRA from other GWDs are its underground location and the cryogenic operation of the four main mirrors. The underground location provides a quiet site with low seismic noise, while the cryogenic operation cools the mirrors down to 20 K, reducing the thermal noises. However, as cooling system components are relatively heavy and in close proximity to the test masses, oscillation of gravity force induced by their vibration, so-called Newtonian noise, could contaminate the detector sensitivity. Therefore, we used the results from the vibration analysis of the KAGRA cryostat at 12K to estimate cooling system Newtonian noise in the 1-100 Hz frequency band.
In this talk, we present methods, considerations, calculations and results of Newtonian noise estimation. Since cryogenics will be a key technology employed in third-generation detectors like Einstein Telescope, the findings can guide the design of the cryogenic infrastructure of these third-generation detectors.
Low-frequency changes of atmospheric pressure contribute to measurement noise of gravity detectors. On one hand, changes of frequency around 0.1 Hz and less cause tilt of the ground and the instrument placed on it. This results undesirable components of long-wavelength and large amplitude in the signal of torsion balances. On the other hand, infrasound waves propagating in the atmosphere changes the density of air, and hence cause changes in the gravitational field. These result undesired movements of the test-masses of gravitational-wave (GW) detectors. One strategy to mitigate the effects of changes of atmospheric pressure on gravity detectors is installing the instruments under the ground.
I will present recent results of infrasound measurements performed at Sos Enattos mine (Sardinia, Italy). This is one of the candidate sites for Einstein Telescope, a proposed third-generation GW detector currently in the preparatory phase. Infrasound is monitored at three levels below the ground, as well as on the surface. I will talk about the mitigation of infrasound in the function of depth, and its relationship with other noise sources.
I will show the effects of atmospheric pressure changes on a gravity gradiometer, the automated Eötvös balance operating 30 meters below the ground at Jánossy Underground Research Laboratory (Csillebérc, Hungary). I will present an experiment, during which controlled tilting of the balance helps to understand the effects of ground tilts.
The 5n-vector ensemble method is a statistical multiple test for the targeted search of continuous gravitational waves from an ensemble of known pulsars. This method can improve the detection probability combining the results from individually undetectable pulsars if few signals are near the detection threshold. In this presentation, I show the results of the 5n-vector ensemble method considering the O3 data set from the LIGO and Virgo detectors and an ensemble of 223 known pulsars. I show no evidence for a signal from the ensemble and set a 95% credible upper limit on the mean ellipticity assuming a common exponential distribution for the pulsars' ellipticitites. Using two independent hierarchical Bayesian procedures, Using two independent hierarchical Bayesian procedures, the upper limits on the mean ellipticity are $2.2 \times 10^{-9}$ and $1.2 \times 10^{-9}$ for the analyzed pulsars.
The MAJORANA DEMONSTRATOR is a neutrinoless double beta decay (0νββ) experiment consisting of ~30 kg of germanium detectors enriched to 88% in $^{76}$Ge and ~14 kg of natural germanium detectors. The detectors are divided between two cryostats and surrounded by a graded passive shield. The DEMONSTRATOR concluded in March 2021 and set a 0νββ half-life limit of $T_{1/2} > 8.3 \times 10^{25}$ yrs based on its full exposure. The experiment achieved one of the lowest background rates in the region of the 0νββ Q-value, 15.7 cnts/(FWHM t y). This background rate, however, was higher than the rate of 2.9 cnts/(FWHM t y) projected by material assays and simulations. This discrepancy arises from an excess of events from the $^{232}$Th decay chain. Background model fits aim to understand the observed $^{232}$Th excess and other deviations from assay-based projections, as well as allow a precision measurement of the 2νββ half-life. Comparisons of the data with simulations indicate the $^{232}$Th excess cannot arise from near-detector components. This is an important finding related to the design and implementation of the LEGEND-200 experiment. The final results of the DEMONSTRATOR are presented along with its latest background model.
*This material is supported by the U.S. Department of Energy, Office of Science, Office of Nuclear Physics, the Particle Astrophysics and Nuclear Physics Programs of the National Science Foundation, and the Sanford Underground Research Facility.
The MAJORANA DEMONSTRATOR concluded its search for neutrinoless double-beta decay in 2021. The experiment operated an array of up to 40.4 kg of germanium detectors, 29.7 kg of which were isotopically enriched in $^{76}$Ge. Thanks to its ultra-low backgrounds, excellent energy resolution, and background rejection capabilites, the DEMONSTRATOR was able to execute a broad program of searches for other rare physical processes. One such process is the double-beta decay of $^{76}$Ge into excited states of $^{76}$Se, which has not been observed before. Six possible decay modes exist, each of which produce events spanning multiple detectors that can be separated from backgrounds. The DEMONSTRATOR previously set world-leading limits in the range of $(0.75-4.0)\times10^{24}$ yrs (90\% C.I.) on the various decay modes of $^{76}$Ge. Since then, we have more than doubled the isotopic exposure and implemented improved analysis techniques that enable improved sensitivity. This talk will present an updated search for double-beta decay of $^{76}$Ge to excited states of $^{76}$Se, and will highlight searches for physics beyond the Standard Model that were conducted by the MAJORANA DEMONSTRATOR.
*This material is supported by the U.S. Department of Energy, Office of Science, Office of Nuclear Physics, the Particle Astrophysics and Nuclear Physics Programs of the National Science Foundation, and the Sanford Underground Research Facility.
Neutrinoless double-beta decay (0νββ) is a key process to address some of the major outstanding issues in particle physics, such as the lepton number conservation and the Majorana nature of the neutrino. Several efforts have taken place in the last decades in order to reach higher and higher sensitivity on its half-life. The next-generation of experiments aims at covering the Inverted-Ordering region of the neutrino mass spectrum, with sensitivities on the half-lives greater than 10$^{27}$ years. Among the exploited techniques, low-temperature calorimetry has proved to be a very promising one, and will keep its leading role in the future thanks to the CUPID experiment. CUPID (CUORE Upgrade with Particle IDentification) will search for the neutrinoless double-beta decay of $^{100}$Mo and will exploit the existing cryogenic infrastructure as well as the gained experience of CUORE, at the Laboratori Nazionali del Gran Sasso in Italy. Thanks to about 1600 scintillating Li$_2$MoO${_4}$ crystals, enriched in $^{100}$Mo, coupled to ~1700 light detectors, CUPID will have simultaneous readout of heat and light that will allow for particle identification, and thus a powerful alpha background rejection. Numerous studies and R&D projects are currently ongoing in a coordinated effort aimed at finalizing the design.
Next-generation neutrinoless double-beta decay searches seek the Majorana nature of neutrinos and the existence of a lepton number violating process. The LEGEND-1000 experiment represents the ton-scale phase of the LEGEND program's search for neutrinoless double-beta decay of $^{76}$Ge, following the current intermediate-stage LEGEND-200 experiment at LNGS in Italy. The LEGEND-1000 design is based on a 1000-kg mass of p-type, inverted-coaxial, point-contact germanium detectors operated within a liquid argon active shield. This approach has achieved the lowest background levels and the best energy resolution at the decay Q value as established by the GERDA and MAJORANA DEMONSTRATOR experiments. The LEGEND-1000 experiment's technical design, energy resolution, material selection, and background suppression techniques combine to project a quasi-background-free search for neutrinoless double-beta decay in $^{76}$Ge at a half-life beyond 10$^{28}$ yr and a discovery sensitivity spanning the inverted-ordering neutrino mass scale. The innovation behind the LEGEND-1000 design, its technical readiness, and discovery potential is presented.
This work is supported by the U.S. DOE, and the NSF, the LANL, ORNL and LBNL LDRD programs; the European ERC and Horizon programs; the German DFG, BMBF, and MPG; the Italian INFN; the Polish NCN and MNiSW; the Czech MEYS; the Slovak RDA; the Swiss SNF; the UK STFC; the Russian RFBR; the Canadian NSERC and CFI; the LNGS and SURF facilities.
Searches for neutrinoless double-beta decay ($0\nu\beta\beta$) offer unique sensitivity to physics beyond the Standard Model and could have implications for key fundamental questions like the origin of the matter-antimatter asymmetry in the universe. Large xenon-based detectors are a leading technology in this field. Among the next generation of $0\nu\beta\beta$ detectors, nEXO takes full advantage of the liquid xenon Time Projection Chamber technology by using a 5 ton detector to probe the $^{136}$Xe $0\nu\beta\beta$ half-life with sensitivity > 10$^{28}$ year. This talk will focus on discussing nEXO’s design, sensitivity, and recent developments. I will conclude with some considerations about challenges, opportunities, and ongoing R&D to extend the liquid xenon technology ton-scale, with the goal to achieve $^{136}$Xe $0\nu\beta\beta$ half-life sensitivities of 10$^{30}$ year or longer.
This work was performed under the auspices of the U.S. Department of Energy by Lawrence Livermore National Laboratory under Contract DE-AC52-07NA27344. LLNL-ABS-848439
There have been significant gains in characterizing neutrino properties in recent years, however the absolute neutrino mass scale continues to be elusive.
The Project 8 collaboration seeks to probe this quantity directly via kinematic analysis of tritium beta decay, using the cyclotron radiation emission spectroscopy (CRES) technique. In order to make neutrino mass measurements with a design sensitivity of 40meV, the Project 8 experiment must use atomic tritium. To create an atomic tritium source suitable for the Project 8 experiment, molecular tritium is thermally dissociated into atomic tritium, which is then state selected and cooled.
I will report on the current status of the atomic source development, covering subsystems for dissociation in coaxial cracker design, followed by accommodation from a surface which is held at O(10) K. The requisite low-field-seeking states are then magnetically guided, evaporatively cooled, and injected into the trap where the atoms decay.
The KATRIN experiment is designed to measure the mass of the electron anti-neutrino by studying the high energy end of the tritium β decay spectrum. In addition, KATRIN is also a well suited instrument to explore the sterile neutrino hypothesis. The existence of sterile neutrinos would cause a kink-like distortion in the spectrum.
Using the same datasets as for active neutrino mass, KATRIN has recently presented new results on the search for sterile neutrinos at the eV scale, complementing the reactor and radioactive source experiments. With an endpoint of 18.6 keV, KATRIN also offers a high potential for the search of sterile neutrinos in the keV range. With data acquired during the 2018 commissioning campaign, KATRIN reported results from a search for keV-scale neutrinos in the restricted mass range of 0.01 to 1.6 keV. The current KATRIN detector is not designed to handle the higher count rate that occurs with a wider mass range. Equipped with the TRISTAN detector KATRIN aims to search for keV sterile neutrinos across the full tritium beta decay spectrum. This detector is currently in production and is scheduled to be operational in KATRIN in 2026.
In this talk, I will present the latest results from KATRIN on the search for sterile neutrinos at eV and keV scales, as well as the ongoing efforts to conduct a high sensitive search for the sterile neutrino at keV scales with TRISTAN.
PROSPECT is a reactor antineutrino experiment consisting of a 4-ton liquid scintillator antineutrino detector divided into an 11x14 array of optically separated segments. The detector was designed to probe the existence of sterile neutrino oscillations and precisely measure the antineutrino spectrum resulting from 235U fission. Data was taken in 2018 and 2019 with a first-generation detector called PROSPECT-I located on the Earth’s surface roughly 7 m from the 85 MW, compact, highly-enriched High Flux Isotope Reactor (HFIR) at Oak Ridge National Laboratory. This dataset has already had a substantial impact by placing stringent limits on sterile neutrino oscillations at the eV scale, setting new direct limits on boosted dark matter models, providing a precision 235U spectral measurement, and demonstrating unique neutrino detection capabilities. During the data collection period, information coming from a small number of PMTs had to be excluded causing an overall statistical impact on previous results. To recover this otherwise lost information, two new data analysis tools, Data Splitting and Single Ended Event Reconstruction, have been implemented, resulting in a multi-period analysis with significant improvements in event reconstruction capabilities and signal-to-background ratios. This presentation will report the final results for the search for eV scale sterile neutrino oscillations using the PROSPECT-I data set.
The SoLid neutrino experiment is a short baseline neutrino experiment installed at 6.2 m from the BR2 reactor, at the SCK-CEN laboratory in Mol, Belgium. The detector consists of 12,800 dual-scintillator cubes (PVT and LiF:ZnS) read out by 3,200 SiPMs. The system is installed inside an ISO-container and shielded against external backgrounds by water and polyethylene slabs. The experiment has operated smoothly from spring 2018 to summer 2020 (Phase-I) and from December 2021 to July 2022 (Phase-II) following an upgrade of the type of SiPMs.
After a period of development of the analysis, the calibration and neutrino selection methods have undergone significant improvements that have resulted in a competitive signal-to-background ratio of approximately 1:3, detection of ~100 antineutrinos per day, and good energy resolution, all necessary for an oscillation analysis and antineutrino spectrum measurement at the level of a few percent based solely on the positron energy.
This talk will present the experiment and detector system, the analysis and the first result of the oscillation analysis using 13 reactor cycles of the phase-I dataset.
We developed a simple small-scale experiment to measure the beta decay spectrum of $^{3}$H. This research aims to investigate the presence of sterile neutrinos in the keV region. Tritium nuclei were embedded in a 1$\times$1$\times$1 cm$^3$ LiF crystal from the $^6$Li(n,$\alpha$)$^3$H reaction. The energy of the beta electrons absorbed in the LiF crystal was measured with a magnetic micro-calorimeter at mK temperatures. We present the current status of the experiment including the energy calibration study. Moreover, we present the project plans for $^{3}$H measurement and their expected sensitivities for keV sterile neutrino search.
The reactor and gallium anomalies of the electron (anti)neutrino disappearance at short baselines have attracted intensive attentions and interests, but have to be resolved yet. In this presentation, I will discuss the status of the reactor and gallium anomalies, both in the framework of 3+1 neutrino oscillation scheme and their possible nuclear-physics interpretations. Future prospect for testing the solution of these anomalies will also be discussed.
This presentation is based on the following publications:
[1] C. Giunti, Y.F. Li, C.A. Ternes, Z. Xin, Phys.Lett.B 829 (2022) 137054, arXiv:2110.06820.
[2] C. Giunti, Y.F. Li, C.A. Ternes, O. Tyagi, Z. Xin, JHEP 10 (2022) 164, arXiv:2209.00916.
[3] C. Giunti, Y.F. Li, C.A. Ternes, Z. Xin, arXiv:2212.09722.
From the discovery of the neutrino to the measurement of $\theta_{13}$, the last unknown neutrino mixing angle, nuclear reactors have proved to be a fundamental tool to study these particles, of which much remains to be unveiled. Measurements involving reactor antineutrinos rely on the prediction of their energy spectrum, a non-trivial exercise involving ad-hoc methods and carefully selected assumptions.
A discrepancy between predicted and measured antineutrino fluxes at a few meters distance from reactors arose in 2011, prompting a series of experimental efforts aimed at studying neutrino oscillation at a baseline that was never tested before. This so-called reactor antineutrino anomaly can, in fact, be accounted for by invoking the existence of new sterile neutrinos at the eV mass scale that participate in the neutrino mixing, an appealing hypothesis tying to other anomalies already observed in the neutrino sector, that opens a door for physics beyond the Standard Model.
With this talk, the author intends to give an overview of the most recent results of the projects involved in the search for reactor antineutrino oscillation at a very short baseline, as well as their implication in our current understanding of the reactor antineutrino anomaly and the eV-scale sterile neutrino hypothesis.
The COST Action: "Cosmic WISPers in the Dark Universe: Theory, Astrophysics and Experiments" (https://www.cost.eu/actions/CA21106/) officially started on November 1st 2022. The aim of this Action is to coordinate and support WISPs searches (on axions, dark photons, etc.) in a synergic way at the boundary between particle physics, astrophysics and cosmology.
We introduce the Action physics cases and the five Working Groups which have been created: WG1 WISPs Model Building, WG2 WISPs Dark Matter and Cosmology, WG3 WISPs in Astrophysics, WG4 Direct WISPs searches and WG5 Dissemination and Outreach. We present activities that we have introduced, from the one at the level of single working groups to schools and workshops open to a large audience.
A link to the CA21106 webpage and information for registration will be given on the poster. CA21106 welcome all scientists interested in topics related to WISPs!
Communicating the science goals and achievements of the ATLAS Experiment is a core objective of the ATLAS Collaboration. This talk will explore the range of communication strategies adopted. We provide an overview of ATLAS’ digital communication platforms, including its website, social media, YouTube and Virtual Visit programme. We also present material and activities designed to engage students and publics of all ages, including books, printable material, events at festivals, public talks and more. Measured effects on target audiences are evaluated in several cases and best practices are shared.
On June 29, a webinar was held by the IceCube Collaboration to announce the detection of the Galactic Plane in neutrinos. The leading institutions were in the US and in Germany. This is the perspective of the German institution TU Dortmund University on the preparation of the event including the production of online material, the preparation of the press conference and lessons-learned from the webinar.
Gravitational wave research exerts the fascination of Astronomy and, at the same time, stimulates the curiosity of fundamental physics on the general public: discoveries and results related to gravitational waves are often in under the spot of global communication, both on media and social media.
This has given rise to opportunities, but also to unprecedented problems, for the large international collaborations that run these experiments, as well as for other equally large astroparticle experiments. On the one hand, there is the complexity of the stories and tools, which can allow the general public to get closer to the contents (e.g. of gravitational physics), be part of its progress, but also of the uncertainty of the knowledge processes. On the other hand, the extraordinary number (hundreds, if not thousands) of researchers that make up these research communities, open new issues: how to manage confidential information within such large groups? How to build a public image recognizable to the research community but also to the general public? How to manage the contradiction between the reality of scientific research as a collective effort and the need for personalization of narratives, for example on social media? How provide quick and immediate answers about complex and uncertain questions? Retracing some recent moments in the public communication of gravitational waves could probably help to shed light on the contemporary issues of communication of fundamental research.
Underground physics has been conducted at the Pyhäsalmi mine in Finland for over 20 years and it was one of the sites in FP7 LAGUNA and LAGUNA LBNO design studies. In 2016, the University of Oulu established the Callio Lab multidisciplinary research centre, which began coordinating scientific activities on-site. Since then, we have hosted and conducted research in disciplines ranging from particle physics and geosciences to underground food production and remote sensing. The operating environment would also suit studies in circular economy and space and planetary sciences, which are being explored by the Callio SpaceLab initiative.
Underground mining ended in 2022 and repurposing of the mine into a pumped hydro energy storage by the Pyhäjärvi town-owned CALLIO - Mine for Business concept will begin. This ensures the underground environment will remain accessible to science and R&D. Together with the easy tunnel and elevator access, low seismicity, which has been observed to decrease dramatically since the conclusion of underground extraction, and the flat 1.4 km overburden (~4000 m.w.e.) the site is a potential candidate for future physics experiments.
Callio Lab is a founding member of the European Underground Laboratories Association, a member of the DULIA network, and an EPOS and national FIN-EPOS research infrastructure.
[1] Joutsenvaara, J. et al. Callio Lab – the deep underground research centre in Finland, Europe J. Phys.: Conf. Ser. 2156 (2022) 012166.
Boulby Underground Laboratory is the UK’s deep underground science facility and one of the few special facilities in the world suited to studies requiring ultra-low background radiation experimental space and/or general access to the deep underground environment. Boulby operates in a working polyhalite and salt mine in the North East of England and hosts a range of science from astroparticle physics (Dark Matter and neutrino studies) to Earth and environmental science, astrobiology and planetary exploration technology development. Boulby also operates its BUGS (Boulby Underground Screening) facility with a range of high sensitivity, ultra low background material screening capabilities. STFC and Boulby Lab are now planning for major expansion of facilities and science at Boulby in the coming decade, working towards a major new facility for next generation astroparticle physics project and more being available from 2030+. This talk will give details of the current Boulby facility and science, and the planned future expansion.
The Southern hemisphere offers a wonderful opportunity for scientists to explore unique initiatives offered by a low level radiation facility. Establishing a deep underground physics laboratory to study, amongst others, double beta decay, geo-neutrinos, reactor neutrinos and dark matter has been discussed for more than a decade within the austral African physicists’ community. The Paarl-African Underground Laboratory (PAUL) is foreseen as an open international laboratory, a unique opportunity for Africa, devoted to the development of competitive science in the region. It has the advantage that the location, the Huguenot tunnel, exists already and the geology and the environment of the site is appropriate for an experimental facility. A report of the most recent developments in the establishment of the PAUL and the envisaged research programs is presented.
Neutrons constitute a significant source of experimental background in rare event searches carried out in underground laboratories. In order to accurately estimate the background contributions affecting these experiments, it is essential to possess a thorough understanding of the underground neutron flux. To that end the High Efficiency Neutron Spectrometry Array (HENSA) has been designed.
HENSA is a detection system based on the Bonner Spheres principle. It consists on several independent 3He neutrons counters which are embedded in moderators with different sizes in order to provide sensitivity in a wide range of neutron energies. Early versions of the has already been used in hall A of the Canfranc Underground Laboratory (LSC) [1, 2], as well as in the shallow underground facility Felsenkeller in Dresden [3].
In this contribution, we present the results of a two-years monitoring of the neutron flux close to setup of the ANAIS-112 experiment in hall B of the LSC. The aim of this measurement is to characterizes the neutron flux with the goal to set a limit on the corresponding effects in the ANAIS background. Various data analysis techniques, including pulse shape discrimination, are discussed. The first results on the spectral reconstruction of the neutron flux will be also reported.
[1] D. Jordán et al., Astropart. Phys. 42 (2013) 1.
[2] S.E.A Orrigo et al., EPC C 82 (2022) 14.
[3] M. Grieger et al., Phys. Rev. D 101 (2020) 123027.
I will discuss a scotogenic model for generating neutrino masses through a three-loop seesaw. It is a minimally extended inert doublet model with a spontaneously broken global symmetry $U(1)'$ and a preserved $\mathbb{Z}_2$ symmetry. The three-loop suppression allows the new particles to have masses at the TeV scale without fine-tuning the Yukawa couplings. The model leads to a rich phenomenology while satisfying all the current constraints imposed by neutrinoless double-beta decay, charged-lepton flavor violation, and electroweak precision observables. The relatively large Yukawa couplings lead to sizable rates for charged lepton flavor violation processes, well within future experimental reach. The model could also successfully explain the $W$ mass anomaly and provides viable fermionic or scalar dark matter candidates.
This paper reports the preliminary design of waveform digitizer “WRX0608A1” for Jinping neutrino experiment at CJPL. Single block digitizer can support 6-channels 1GSPS, 13-bit sampling. The WRX0608A1 is a 12-layer PCB, hosting 6 ADCs, one FPGA (Xilinx Kintex 7 XC7K325T), one PLL (TI LMK04803), one DDR3 SODIMM (Micron MT8KTF51264HZ-1G9P1), one re-driver (TI DS125BR820), two QSFP interfaces and other parts. The ADC’s effective number of bits (ENOB) was actually tested using SMA100B from R&S®, band-pass filter Q70T-10M-1M-50-720A and low-pass filter J97T-14M-50-69A from TTE. The results show that under 10MHz sine wave, ENOB>10bit, which means that it can meet the needs of neutrino experiments. The open area and the open UI of QSFP all eight lanes’ eye diagram are better than 3900 and 50%, respectively. When the BER is 6.393e-15, there is no bit error. Similarly, we used two WRX0608A1, one trigger board and one eight-slot backplane for backplane high-speed signal integrity testing. Under the lane speed of 10.3125 Gbps, there is no bit error in the test. The joint debugging experiment of the waveform digitizer and the detector and the research on the trigger algorithm are in progress.
The SNO+ Experiment is a versatile multipurpose neutrino detector situated at SNOLAB, with the primary goal of searching for neutrinoless double beta decay (0νββ). After a successful operating phase as a water Cherenkov detector, the SNO+ target medium was switched to liquid scintillator to increase the light yield of the detector, thereby enabling a much richer physics programme.
In addition to ongoing measurements of reactor antineutrinos, solar neutrinos, geoneutrinos, supernova neutrinos, and other exotic phenomena, the SNO+ experiment is preparing for the deployment of tellurium within the scintillator, thereby enabling a 0νββ search. A major advantage of the experiment is the capability for backgrounds within the 0νββ region of interest to be well-understood prior to the addition of the tellurium (i.e. target out). This poster will discuss the target out analysis to be used for the upcoming 0νββ search phase of the SNO+ experiment.
Effects beyond-standard oscillation (BSO) are being studied as they can modify the framework of the standard oscillation due to second-order contributions. In this work, we investigate the sensitivity of the DUNE experiment to observe such BSO effects as we increase their intensity, for which we include different BSO hypotheses. The BSO hypotheses considered in this work are: neutrino decay (invisible and visible), non-standard interactions, violation of the equivalence principle, and quantum decoherence. We systematically evaluate DUNE's ability to distinguish between different BSO hypotheses, assigning one of them as the true signal and another as the test signal. The CP-violating phase parameter, $\delta_{CP}$, may have potential distortions with respect to the measured value using an incorrect BSM hypothesis. Even when the BSO scenarios are almost indistinguishable from each other, the measured value of $\delta_{CP}$ can be very different from the value used in the theoretical hypothesis.
The importance of predicting neutron multiplicity associated with neutrino interactions has increased. This study focuses on residual nuclear deexcitation, which contributes to neutron multiplicity, and aims to accurately predict this process.
Liquid scintillator (LS) detectors such as KamLAND can detect ~100% of 2.2 MeV gamma rays emitted by neutron capture. They are suitable to observe inverse beta decay. This is useful in searching supernova relic neutrinos (SRN), because atmospheric neutrinos, serious backgrounds, can be reduced by requiring the presence of a neutron. Super-Kamiokande (SK), a water Cherenkov (WC) detector, is improving detection efficiency by dissolving Gd. As well as LS detectors, neutron multiplicity is a hot topic.
However, prediction is very challenging because of complex nuclear effects. Furthermore, existing neutrino interaction simulators usually do not describe residual nuclei's deexcitation. Neutrino knockout nucleons in the nucleus leaving it often with high excitation energies. The nuclei often emit neutrons in going to the ground state. A prediction with a nuclear reaction simulator, TALYS, has been started. A recent comparison with observed data was available KamLAND data[1]. Since its uncertainty was large, it needs to be improved for future experiments. Various studies are ongoing: oxygen targets for WC detectors and implementation in neutrino interaction simulators.
[1] S. Abe et al., Phys. Rev. D 107, 072006 (2023)
The analysis of cryogenic detector data is known to be challenging for any experiment. The main difficulty for the analysis of these detectors is the background rejection since they suffer from the presence of several different pulse shapes which need to be discriminated down to very low SNR
conditions.
Background reduction is particularly important for the NUCLEUS experiment since the aim is to produce ultra-low threshold ( ~ 20 eV) cryogenic detectors to measure coherent elastic neutrino-nucleus scattering at the Chooz nuclear power plant. The low threshold is necessary due to the low
nuclear recoil signal produced which is under 1 keV.
In this poster the data analysis procedure performed for the NUCLEUS experiment with the DIANA analysis framework is presented along with several upgrades made to the framework since the initial implementation in the CUORE neutrinoless double-beta decay experiment.
Flavor-dependent long-range leptonic force mediated by an ultralight and neutral gauge boson $Z'$ associated with $L_\mu -L_\tau$ symmetry constitutes a minimal extension of the Standard Model. Assuming $Z-Z'$ mixing, we study the physical consequences of such long-range force in the oscillation of atmospheric neutrinos. We show that the proposed atmospheric neutrino detector ICAL will be able to put tight constraints on such long-range force due to its capabilities of detecting neutrino and antineutrino separately with wide ranges of energies and baselines. The expected upper limit on the parameter related to coupling strength of this long-range force at $3\sigma$ is $2.82\times 10^{-51}$ using 500 kt$\cdot$yr exposure of ICAL. Also, we study the possible impact of this long-range force in the expected measurement of atmospheric neutrino oscillation parameters and mass ordering at the ICAL.
The long baseline neutrino experiment T2K has successfully used Monte Carlo simulations for the neutrino flux predictions in both near and far detectors, which are essential inputs for different neutrino oscillation and cross section analyses. However, the current simulation software is based on FLUKA and the no-longer maintained simulation package GEANT3, which is becoming difficult to support. A replacement beam simulation using the GEANT4 software package is in development, aiming to describe the physical processes from the primary proton interactions in the T2K target to the decay of hadrons and muons, producing neutrinos for the flux predictions at both near and far detectors. The T2K flux simulation is generally tuned using measurements from the NA61/SHINE spectrometer of $\pi^\pm$, $K^\pm$, and proton differential yields emitted from a T2K replica target, and those measurements can also be used to validate the new simulation software. We present the recent simulation results for the validation with NA61/SHINE data, the neutrino flux predictions, and comparisons to the current FLUKA/GEANT3 simulations.
The LEGEND Collaboration advances an experimental program to search for the neutrinoless double-beta decay of $^{76}$Ge.
LEGEND-200, the first stage of this program, recently completed its commissioning process at LNGS in Italy. About 140~kg of $^{76}$Ge-enriched high-purity germanium detectors immersed in liquid argon are now continuously taking low background data.
The LEGEND experiment integrates the advanced technology of the germanium detectors used in the \textsc{Gerda} and \textsc{Majorana} experiments. They are well suited for $\gamma$-rays measurements at the MeV energy scale, yielding high detection efficiency.
The crystal growing procedure results in naturally low internal radioactivity and is a well-established technology. A precise understanding of the behavior of the germanium detectors is fundamental to determine their optimal operational parameters and it necessitates extensive detector characterization.
This poster will present the latest state-of-the-art approach to the production chain, the characterization measurements, and the performance of germanium detectors installed in LEGEND-200 so far.
This work is supported by the U.S. DOE and the NSF, the LANL, ORNL and LBNL LDRD programs; the European ERC and Horizon programs; the German DFG, BMBF, and MPG; the Italian INFN; the Polish NCN and MNiSW; the Czech MEYS; the Slovak SRDA; the Swiss SNF; the UK STFC; the Russian RFBR; the Canadian NSERC and CFI; the LNGS, SNOLAB, and SURF facilities.
LEGEND-200 is the first phase of LEGEND, a $^{76}$Ge-based experiment designed to observe a lepton number violating process: neutrinoless double-beta $(0\nu\beta\beta)$ decay. Observation of this process would demonstrate neutrinos to be Majorana particles. The first 101 enriched $^{76}$Ge detectors, with a total mass of 142 kg, have been installed and are currently taking data at the Laboratori Nazionali del Gran Sasso (LNGS), Italy. A comprehensive simulation campaign is underway to study and model the background contributions from various components in the experimental setup. In this poster, we will present the current results of the simulation campaign as well as a preliminary background model for the LEGEND-200 experiment.
This work is supported by the U.S. DOE and the NSF, the LANL, ORNL and LBNL LDRD
programs; the European ERC and Horizon programs; the German DFG, BMBF, and MPG;
the Italian INFN; the Polish NCN and MNiSW; the Czech MEYS; the Slovak SRDA; the Swiss SNF; the UK STFC; the Russian RFBR; the Canadian NSERC and CFI; the LNGS, SNOLAB, and SURF facilities.
The Jiangmen Underground Neutrino Observatory (JUNO) is a multipurpose neutrino experiment that aims to determine the neutrino mass ordering (NMO) and to precisely measure the oscillation parameters using reactor neutrinos. Atmospheric neutrinos can also contribute to the NMO sensitivity with a complementary approach: using the matter effects on neutrino oscillations. This poster will present the recent Monte Carlo studies of atmospheric neutrino event selection and classification at JUNO, which will enhance the oscillation sensitivity by using novel data analysis techniques. Specifically, the PMT charge and time information from both the Central Detector and the Water Pool Veto detector will be used to suppress cosmic muon backgrounds and identify the different flavors. The multiplicity of spallation neutrons and Michel electrons associated with the primary atmospheric neutrino interactions is expected to help separate neutrinos from antineutrinos.
CUPID (CUORE Upgrade with Particle IDentification) is a next-generation experiment planning to search for the
neutrinoless double-beta decay with bolometric detectors, featuring 250 kg of $^{100}$Mo. The detector will be operated
in a custom cryostat at the Gran Sasso National Laboratory (Italy), which is currently hosting the
CUORE experiment, a large array of TeO$^{2}$ bolometers. CUPID will exploit scintillating bolometers consisting
of Li$_2^{100}$MoO$_4$ crystals facing thin Ge-wafer-based bolometric light detectors. The light detectors will allow for
full discrimination of the alpha background. Since the various background contributions can limit the experiment's sensitivity, all the components are being carefully investigated and benchmarked in view of the CUPID design.
A critical contribution to the CUPID background comes from the pile-up of two-neutrino-double-beta-decay
events of $^{100}$Mo. This can be mitigated by the use of enhanced light detectors based on the Neganov-Luke-Trofimov
(NTL) effect, which provide fast signals and a high signal-to-noise ratio. A demonstrator with 10 Ge NTL light detectors
has been measured in an underground cryogenic facility in Canfranc (Spain). The light detectors have been
characterized in terms of sensitivity, energy resolution, and noise power spectrum. This test
allows us to evaluate the feasibility of employing NTL LDs in the CUPID experiment and to assess the sensitivity
reach of CUPID with the enhanced light channels.
Xenon-based detectors are powerful tools in the search for low energy signatures of new physics. Here we report on experimental results that open up a new channel for rare event searches in these detectors: MeV-scale charged-current interactions on $^{136}$Xe nuclei. These interactions populate low-lying 1+ excited states in $^{136}$Cs, which then relax to the ground state. We have performed measurements of $\gamma$ rays produced by $(p,n)$ reactions on $^{136}$Xe, providing the first data on the gamma ray emission from the relevant excited states in $^{136}$Cs. We identify two isomeric states with O(100)~ns lifetimes, enabling delayed-coincidence analyses that can dramatically suppress backgrounds. These results may enable xenon-based detectors to perform background-free measurements of solar $^{7}$Be and CNO neutrinos, as well as achieve unprecedented sensitivity to dark matter particles interacting with nuclei through new charged-current-like interactions.
KM3NeT is a deep-sea neutrino observatory under construction at two sites in the Mediterranean Sea. The ARCA telescope (Italy), aims at identifying and studying TeV-PeV astrophysical neutrino sources, while the ORCA telescope (France), aims at studying the atmospheric neutrino oscillations in the few GeV range. Since they are optimised in complementary energy ranges, both telescopes can be used to do neutrino astronomy from few MeV to few PeV, despite of their different primary goals. The KM3NeT observatory takes active part to the real-time multi-messenger searches. These searches allow to study transient phenomena by combining information from the simultaneous observation of complementary cosmic messengers with different observatories. In this respect, a key component is the real-time distribution of alerts when potentially interesting detections occur, in order to increase the discovery potential of transient sources and refine the localization of poorly localized triggers, such as gravitational waves. The KM3NeT real-time analysis framework aims at performing the reconstruction of all ARCA and ORCA events, searching for spatial and temporal coincidences around received alerts after having filtered them, selecting a sample of interesting events to send alerts and performing the core-collapse supernova analysis. This contribution deals with the current status of the KM3NeT real-time analysis framework and its first results.
Slow organic and water-based liquid scintillators are currently developed and characterized for future large-scale neutrino experiments such as Theia. One goal of these new scintillators is to separate Cherenkov light from scintillation light in a detector. By that, the spatial information improved while keeping the excellent energy resolution of proven organic mixtures.
This contribution focuses on scintillation time profile studies of novel liquid scintillators. We performed liquid scintillator characterization experiments using a pulsed neutron beam at the CN accelerator of INFN Laboratori Nazionali di Legnaro. At different beam energies ranging from 3.5 MeV to 5.5 MeV, the fluorescence time profile of recoil protons was recorded. Differences in the time profiles after gamma and neutron excitation open the window to perform pulse shape discrimination and therefore advance the ability to distinguish the neutrino signal from backgrounds.
CUORE is a ton-scale experiment, consisting in an array of 988 cryogenic calorimeters, designed for the search of the neutrinoless double beta ($0\nu\beta\beta$) decay of $^{130}$Te. One of the crucial parameters in defining the sensitivity to such a rare event is the detectors energy resolution.
CUORE is taking data since 2017. During the years, we observed that the energy resolution is influenced by a low-frequency seismic noise, which contributes in the same bandwidth of particle signals.
This contribution will report a novel multi-detector analysis involving CUORE cryogenic detectors, in-situ high-sensitivity seismometers and marine measurements in the Mediterranean Sea, highlighting the correlation between the noise of CUORE detectors below 1 Hz and marine microseismic events.
Such correlation induces changes of the low-frequency noise of the detectors when weather and marine conditions of the Mediterranean Sea change.
The study of the response of CUORE detectors to marine microseismic events opens the possibility to an improvement of the seismic suspension system of the CUORE cryostat, which will be used also by CUPID, the next-generation cryogenic experiment for $0\nu\beta\beta$ decay searches.
The Baikal Gigaton Volume Detector (Baikal-GVD) is a 3-dimensional array of optical modules located 1366 metres deep in Lake Baikal. It is designed to detect high-energy neutrinos coming from galactic and extragalactic sources. Currently (year 2023) the detector consists of 3456 optical modules grouped into clusters. Each cluster is connected to shore with individual optoelectric cable (~ 6km) and thus its operation is independent of other clusters in the detector.
The Cherenkov radiation produced by secondary charged particles originated from neutrino interactions creates in the water different kinds of light signatures. According to the event topology, it is possible to distinguish between types of the neutrino interactions. Cascade events are produced in charged current electron and tau neutrino interactions and neutral current interactions of all-flavour neutrinos. The most abundant background in the cascade channel is produced by discrete stochastic energy losses along the atmospheric muon track. In this presentation, the results on the suppression techniques of these background cascades will be presented.
The Jiangmen underground neutrino observatory (JUNO) is a neutrino project under construction with a 20-kton liquid scintillator detector, which includes 20000 20-inch PMTs(15000 MCP-PMTs and 5000 dynode-PMTs). As a key component of JUNO detector, the performance of 20-inch PMTs(LPMTs) has a significant impact on the energy and timing measurement and the vertex reconstruction of anti-electron neutrino. So far, all LPMTs passing the acceptance test have been potted and some potted LPMTs have been randomly selected to test with container system in zhongshan. At the JUNO site, the installation of LPMTs has started. It is necessary for LPMTs to pass a functionality test before installation and carry out regular light-off tests to check the status of the installed LPMTs during the installation process. This poster presents the test results from the container system including relative detection efficiency, gain, dark count rate, charge, etc., and the light-off tests at JUNO site.
The contribution reports about the commissioning of an ultra low-level 𝛾-ray counting setup in the shallow-underground laboratory Felsenkeller in Dresden, Germany. It includes a high-purity germanium detector of 163$\,$% relative efficiency within passive and active shields. The passive shield consists of 45$\,$m rock overburden (140 meters water equivalent), 40cm of low-activity concrete, 15 cm of high purity lead, 10 cm of oxygen-free radiopure copper, and an anti-radon box. The active veto is realized by five large plastic scintillation panels surrounding the setup. All together, these shieldings attenuate the remaining background rate down to 116(1)$\,$kg$^{−1}$d$^{−1}$ in an energy interval of [40$\,$keV;2700$\,$keV]. This is the lowest background of any HPGe detector in Germany, among the lowest worldwide, and enables studies of samples well below 1$\,$mBq. In addition to the design of the setup, the underlying analysis techniques will be presented.
To study rare nuclear processes like neutrinoless double beta decay or dark matter scattering of atomic nuclei, a sensitive detector with a very low background is needed. To reduce the background components from cosmic rays, such a detection system is often located deep underground with an anti-cosmic veto. The background of the experiment is therefore dominated by natural radioactivity in the construction materials of the detector and surrounding area. To eliminate this contribution, radioactive pure materials have to be selected for construction and very high sensitivity methods are required for the determination of radiation content. A special challenge represents naturally occurring long-lived isotopes of uranium and thorium, that form decay chains. Several methods can be used for the determination of these radionuclides; however, the best detection limit can be achieved with mass spectrometry methods. Preliminary results from using AMS (accelerator mass spectrometry) and ICP MS (inductively coupled plasma mass spectrometry) will be presented.
Understanding the internal radioactive background contributions in its 20-kiloton liquid scintillator (LS) target is essential for the success of the JUNO reactor neutrino experiment. OSIRIS is a 20-ton radiopurity detector at the end of JUNO’s LS purification chain screening 1/10 of the LS during the filling of JUNO and verifying that the radiopurity requirements are met. After the filling and combined with the existing extensive LS purification infrastructure, OSIRIS will serve as an excellent testbench for different kinds of LS studies and especially in the development of JUNO’s future physics program. So far considered scenarios vary from long term LS stability or double beta decay isotope loading tests to standalone precision measurement of the solar pp neutrino flux. To maximize the outcome of such measurements, cost-efficient improvements of the OSIRIS detector are required. For example, to improve the light collection uniformity, the cylindrical photodetector configuration will be changed to a spherical one. Improvement in light collection is achieved by assembling light concentrator cones and adding extra PMTs. Addition of external shielding will help to suppress the external gamma ray background in the central volume of the detector. This work discusses more in detail the foreseen improvements and physics cases of OSIRIS upgrade.
The international CUPID-Mo collaboration for 0νββ experiment uses the NTD photothermal readout system. Based on the exsiting scheme and experience, we plan to use the advanced TES photothermal dual readout detection for Cupid-China 0vββ Experiment next stage. This report focuses on the regulated preparation of TES superconducting thin films working in the temperature range of 10-20 mK. Also, the model construction for the whole physical process of TES photothermal signal reading is explored in this topic. The core structures of TES photothermal detector unit will include: LMO crystal, TES photothermal detector, Si substrate, LMO and weak thermal support structure of photon detector, reflective layer, heat sink and mechanical shell.
Through the 0νββ signal and background discrimination study, we carry out the physical design, preparation and test characterization of TES detector. By constructing and simulating the whole physical process model of TES detector, we can master the influence of TES components parameters on the overall performance of the detector, so as to optimize the TES design.
The Karlsruhe Tritium Neutrino (KATRIN) experiment has the goal to determine the effective electron antineutrino mass with a sensitivity of 200 meV/$c^2$ @90%C.L. The main spectrometer background is the strongest limit on the sensitivity. It consists presumably of low energy electrons which arrive at the detector with small angles contrary to the signal electrons. Designing an angular selective detector shows great potential in increasing the sensitivity of the KATRIN experiment.
The concept of active-transverse-energy filters (aTEFs) has been developed
by members of the KATRIN collaboration. It proposes micro-structured detector configurations that are sensitive to the angular of the detected electrons. At the moment, two different approaches are under investigation. One of it is the idea of an aTEF-detector based on a plastic scintillator that is read out by a CMOS-based single-photon-avalanche-diode (SPAD) array (scint-aTEF).
This poster gives an overview of the basic concept of a scint-aTEF. It includes design studies and presents first prototype structures manufactured via 2-photon-absorption lithography (3D-printing).
In the past years, the increasing interest in the search for neutrinoless double beta decay ($0\nu\beta\beta$) brought the collection of an impressive amount of two-neutrinos double beta decay ($2\nu\beta\beta$) data, opening the possibility to investigate exotic $2\nu\beta\beta$ decays. In this category we include all those processes not allowed by the Standard Model (SM) and whose signal could be detected by analyzing the entire $2\nu\beta\beta$ spectral shape (e.g. the Majoron emitting decays or the violation of the Lorentz invariance in the neutrino sector). Nowadays, the data collected with the actual experiments allowed to set stringent limits on many of these beyond the SM processes. In the future, the next-generation experiments will further increase the available statistic.
Nevertheless, the unavoidable background induced by the standard $2\nu\beta\beta$ represents an intrinsic limit in the search for these processes and its fluctuations could easily mimic the new physics signal. In this contribution, we show the possibility of discovery for such processes. In particular, we show the results obtained from a numerical study performed on different isotopes, going through the relation between the expected signal strength and the experimental exposure.
The CUORE (Cryogenic Underground Observatory for Rare Events) experiment at Gran Sasso National Laboratory in Italy primarily searches for neutrinoless double-beta decay of $^{130}$Te. The CUORE detector consists of a close-packed array of 988 TeO$_2$ calorimetric detectors cooled to ~10 mK using a custom-built cryogen-free dilution refrigerator. The experiment is the first to demonstrate stable operation of a tonne-scale milli-kelvin cryogenic calorimeter. We present the analysis techniques used for the latest CUORE data release, focusing on the methods that have been updated relative to our 1 tonne-year analysis. We describe the analysis chain, event selection, and our evaluation of the detector response.
HALO, the Helium and Lead Observatory, has been operating at SNOLAB for eleven years as a low-maintenance, high-livetime supernova neutrino detector. Since October 2015 HALO has been providing low threshold and very low latency supernova alarms to the SuperNova Early Warning System (SNEWS) coincidence servers. The HALO detector is principally composed 79 tonnes of lead, from a decommissioned cosmic ray station, and is instrumented by 368 m of SNO’s ultra-low activity He-3 neutron counters. Supernova neutrinos interacting with the lead target may produce one or two neutron emission through CC or NC excitation of the lead nuclei. HALO detects these neutrons with an average efficiency of 28% and an extended burst of detected neutrons would be consistent with a galactic supernova explosion. The background detected neutron rate in HALO, from various sources, is 15 mHz. Two prompt sources of neutron bursts are muon spallation events (the low cosmic ray muon rate in SNOLAB results in close to two muons per day traversing HALO), and spontaneous fission of U-238 built into HALO. With a neutron thermalization and capture time of 200 usec these prompt bursts are not confused with supernova candidate events. As a large, low-background, and long-running lead-based neutron detector there is an interest in exotic prompt signatures that HALO might have sensitivity to. The collaboration will present its first, preliminary, neutron multiplicity distribution from a reasonably large dataset.
Coherent Elastic Neutrino-Nucleus Scattering, also known as CEvNS, describes the physical process of atomic nucleus scattering with neutrino as a whole, and the scattering cross section is approximately proportional to the square of atomic nucleus neutron number. The research on CEvNS has important scientific significance and application value. The RECODE project (Reactor neutrino COherent scanning Detection Experiment) is a recently proposed experimental plan, which uses two sets of high-purity germanium arrays to jointly measure and accurately measure the CEvNS process of reactor neutrino. The high-purity germanium technology used comes from the PPC germanium detector technology developed by CDEX in dark matter experiments. The PPCGe has significant advantages such as low energy threshold, low background, and good long-term stability et. al., which key performance parameters have been confirmed and tested in CDEX's long-term dark matter experiments. This talk will introduce the RECODE experimental plan and expected results.
SuperNEMO is searching for the hypothesised lepton-number-violating process, neutrinoless double-beta decay (0vbb). The detector is based on the tracker-calorimeter technique, where the trajectories of the charged particles are first reconstructed, before the energies of the electrons being measured. The SuperNEMO Demonstrator is currently taken data with the full tracker and calorimeter.
The search for this very rare process implies a crucial reduction of all backgrounds, either originating from the allowed in the Standard Model double-beta decay with two neutrinos emission or from the natural radioactivity. Due to their high energy release, two isotope decays, if present in the double beta sources, could contribute : Thallium 208 and Bismuth 214. Moreover the contamination of the tracker with Radon 222 could lead to Bi-214 contamination on detector components adjacent to the double-beta source, which could mimic decays in the source. To render this contribution negligible, our goal is to keep radon activity in the tracker below 0.15mBq/m3.
To measure this activity, we look for the classic Bi-Po signature of Bi-214 decay, which emits electron followed by an alpha particle. Our selection of these events in the SuperNEMO Demonstrator is presented, as well as a preliminary measured activity for the tracker.
The discovery of neutrinoless double beta decay (0νββ) would be a huge step in the understanding of the nature of the neutrino. SuperNEMO is an experiment designed to search for 0νββ, whose demonstrator module is located in Modane Underground Laboratory in France (4800 m.w.e). It uses a unique technique combining a tracker and a segmented, scintillator-based calorimeter that allows us to unambiguously identify the two final-state electrons and measure their time and energy. It aims to achieve an ultra-low background level of < 10-4 events/(keV.kg.yr) and its topological reconstruction allows us to probe double-beta decay mechanisms.
The main calibration method uses conversion electrons from 207Bi sources that can be automatically deployed in the centre of the detector. A tracking algorithm based on the Legendre transform is being developed to reconstruct tracks. By combining tracker and calorimeter information, detailed studies of the energy response will be performed to evaluate effects such as non-uniformity and non-linearity of the scintillator making up the calorimeter, and energy losses in the tracker. Some preliminary measurements using the first data from the Demonstrator will be presented.
LEGEND-1000 is a next-generation ton-scale experiment searching for neutrinoless double beta decay of $^{76}$Ge using p-type, high-purity germanium detectors. The experiment is planned for 1000 kg of Ge detectors enriched to more than 90$\%$ in $^{76}$Ge.
The experiment is going to be installed in an underground laboratory (SNOLAB at 6000 mwe or LNGS at 3800 mwe) to reduce direct and induced backgrounds from cosmic rays.
While standard analysis techniques are very effective in removing prompt backgrounds, muon-induced events, associated with the production of long-lived isotopes in Ge detectors, require the application of delayed coincidence cuts between muon veto, liquid argon veto, and the Ge detectors.
We present selected details of the new active veto for LEGEND-1000 at LNGS. The goal is to increase the instrumented liquid argon volume in order to enhance the delayed coincidence cut efficiency.
We will also discuss various readout options considered and related preliminary simulation results.
This work is supported by the U.S. DOE and the NSF, the LANL, ORNL and LBNL LDRD programs; the European ERC and Horizon programs; the German DFG, BMBF, and MPG; the Italian INFN; the Polish NCN and MNiSW; the Czech MEYS; the Slovak SRDA; the Swiss SNF; the UK STFC; the Russian RFBR; the Canadian NSERC and CFI; the LNGS, SNOLAB, and SURF facilities.
Coherent elastic neutrino-nucleus scattering (CEνNS) is a process well understood within the Standard Model. A high-precision study of CEνNS can be used to probe the Standard Model and reveal potential non-standard interactions. NUCLEUS is an experiment aiming to conduct such a high-precision measurement at the EdF Chooz-B nuclear power plant in France. The experiment is currently under construction, and simulations of ambient and intrinsic backgrounds help to predict the sensitivity to CEνNS and to optimise the background management capabilities of the experimental setup.
A considerable source for ambient background are neutrons induced either by cosmic rays in the atmosphere or by fast muons that directly hit the setup. With energies above a few MeV, such neutrons can trigger events in the experiment’s energy region of interest (ROI; up to 100 eV) with rates comparable to the predicted CEνNS signal. Their study is therefore of high interest.
A high-statistics simulation has been conducted, starting from ambient particles. The energy spectra deposited in NUCLEUS’s cryogenic CaWO$_4$ and Al$_2$O$_3$ targets are used to estimate the shielding power of the building. In a future step, the shielding power can be included in accurate sensitivity predictions of the experiment.
I will outline the procedure of a high-statistics ambient neutron and muon study. The resulting count rates in the experiment’s ROI and their impact on NUCLEUS’s sensitivity to CEνNS will be discussed.
The ACCESS (Array of Cryogenic Calorimeters to Evaluate Spectral Shapes) project aims to develop cryogenic calorimeters to perform a precise study of the spectral shape of forbidden β-decays. These strongly suppressed processes can help to clarify the long-standing issue of the axial coupling constant ($g_A$) quenching involved in nuclear physics calculations. Moreover, such rare decays are also a common source of systematic uncertainty in Dark Matter and Neutrinoless Double Beta Decay experiments, where detailed knowledge of the shape of the background spectrum is required.
In this contribute, we will present a brief review of the ACCESS research program, aiming to study both natural ($^{113}$Cd and $^{115}$In) and synthetic isotopes ($^{99}$Tc). The main attention will be dedicated to the current status of the research program and recent promising results achieved for $^{115}$In with an InI-based cryogenic calorimeter. The physics data acquired over 300-h-long cryogenic run will be presented. The InI detector demonstrates an excellent compromise to optimize simultaneously the signal yield and the detector response function, avoiding efficiency loss induced by a high counting rate. Further measurements of the InI crystal to collect higher statistics are on the schedule.
Baikal Gigaton Volume Detector (Baikal-GVD) is a neutrino telescope being constructed in the deepest freshwater lake in the world – Lake Baikal. It is designed to observe astrophysical neutrinos through detection of Cherenkov radiation emitted by the products of neutrino interactions. The Baikal-GVD is a three-dimensional array of photomultiplier tubes (contained in optical modules) arranged on vertical strings. Currently (2023), it consists of 3456 optical modules.
One of the Cherenkov light topologies that can be created in the charged current interaction of tau neutrino is called double cascade. This signature is produced if tau lepton originating in charged current tau neutrino interaction decays into electron or hadrons. Detection of high-energy tau neutrinos is of crucial importance because it provides a direct method for identification of astrophysical neutrinos, since the production rate of high-energy tau neutrinos in the atmosphere is negligible. In this contribution a technique for the reconstruction of double cascades will be presented.
The construction of a worldwide network of gigaton-scale neutrino telescopes aims to address multiple open questions in physics, such as the origin of astrophysical neutrinos and the acceleration mechanism of high-energy cosmic rays. Besides astrophysics, neutrino telescopes probe center-of-mass energies similar to colliders, offering an additional window into high-energy particle interactions.
Currently, there are no publicly available simulation tools for these detectors, leading to duplication in effort for each experiment and hindering the testing of theoretical models.
While these detectors are built in ice or water at different locations, they operate on the same detection principle: Using multiple optical modules to detect Cherenkov photons emitted by charged particles.
Using this, we developed Prometheus, an open-source simulation tool that offers a common simulation chain for all neutrino telescopes. It can inject neutrinos, propagate their interaction products, and model the amount of light reaching the optical modules of a user-defined detector in either ice or water. We will show its runtime performance, highlight successes in reproducing simulation results from multiple ice- and water-based observatories, and discuss simulation sets that we have made publicly available for various detectors.
The current technology of thermal detectors for rare events physics is based on large cryogenic calorimeters read with NTD thermistors (es. CUORE, CUPID). Measuring the energy deposition via the heat release in the crystals allows for optimal energy resolutions when the detectors are operated at 10mK. In case of scintillating crystals, a double readout of heat and scintillation light allows for a discrimination between alpha and beta/gamma events. The light detectors are usually Ge or Si wafers, operated also as thermal detectors. A fundamental aspect for the CUPID detectors is the improvement in the collection and detection of scintillation light.
A different realisation of the NTD thermistor electrodes can affect the sensitivity of these thermal sensors; 10B/11B ion isotopes of the NTD electrode implants have a different specific heat at low temperatures which is inversely correlated with the thermal rise for a given energy release. New strategies for coupling the NTD thermistor to the absorber can also improve the system sensitivity and reduce the thermalisation time constants; eutectic bonding and silicate bondings are tested and compared with the traditional glue coupling. Moreover, a reflective coating of the absorber surfaces can increase the light collection, such as an Al layer deposited on the Li2MoO4 crystals.
We will show the performance measured in the Milano Cryogenic Lab of several thermal detectors realised with the mentioned novel techniques for CUPID R&D.
Pre-supernova neutrinos are released by thermal pair production and/or weak interaction prior to supernovae.
These neutrinos can offer a unique possibility for early alarm system prior to supernovae for astronomical detectors, including gravitational wave detectors and neutrino detectors.
KamLAND is a 1-kiloton liquid scintillator neutrino detector located in Japan that employs delayed coincidence selections of inverse beta decay to detect anti-electron neutrinos with low background condition.
Its capability to detect pre-supernova neutrinos from nearby stars has been leveraged for an early warning system since 2015.
The original system was optimized using the only theoretical model at the time.
In this poster, we present re-optimization of the system with latest theoretical models and new possibilities to use time evolution of expected signal.
The SK-Gd experiment, in which Gd is added to Super Kamiokande, is also sensitive to pre-supernova neutrinos. We also show a combined alarm system with SK-Gd experiment, which plays a key role to improve detectable range and alarm time.
The Jiangmen Underground Neutrino Observatory (JUNO) is a next-generation neutrino experiment under construction in South China. JUNO has great potential to detect atmospheric neutrinos with good flavor identification capability thanks to the large-scale and high photo-coverage liquid scintillator (LS) detector. There will also be $\nu_\tau$ produced by the oscillation of the other two flavor neutrinos propagating through the earth, besides the primary atmospheric $\nu_e$ and $\nu_\mu$. The search for atmospheric $\nu_\tau$ appearance in an LS detector, which complements to that in Cerenkov detectors like Super-K, ORCA or IceCube, can provide an unambiguous confirmation of three-flavor neutrino oscillations. In the meanwhile, the measurement of the inclusive charged-current $\nu_\tau$ cross section can examine the consistency with the Standard Model prediction. This contribution will mainly focus on two parts: the study of $\nu_\tau$ interaction features in LS, and the developed methods to identify $\nu_\tau$ from atmospheric neutrino background in JUNO.
LEGEND-200 is the first phase of a two-phased experiment pursued by the LEGEND Collaboration to search for neutrinoless double-beta decay ($0\nu\beta\beta$) in Germanium-76 (Ge-76). Discovery of $0\nu\beta\beta$ would demonstrate lepton-number non-conservation while providing critical insight into the nature of the neutrino and its role in the universe. LEGEND-200 recently completed commissioning at the Laboratori Nazionali del Gran Sasso (LNGS), Italy. For initial operations, 101 detectors (142 kg) enriched to ~88$\%$ in Ge-76 were installed. This poster focuses on the extraction of physics signals from Ge-76 detectors and veto systems using the versatile FlashCam digitizers. An overview of the Object-orientated Real-time Control and Acquisition (ORCA) software controlling the data acquisition and storage process is presented. There is also an independent slow controls system providing control and monitoring of LEGEND-200’s cryo and electronics subsystems. Aspects of operations, including control, daily monitoring, and weekly calibrations with Thorium-228 sources is also discussed. This work is supported by the U.S. DOE and the NSF, the LANL, ORNL and LBNL LDRD programs; the European ERC and Horizon programs; the German DFG, BMBF, and MPG; the Italian INFN; the Polish NCN and MNiSW; the Czech MEYS; the Slovak SRDA; the Swiss SNF; the UK STFC; the Russian RFBR; the Canadian NSERC and CFI; the LNGS, SNOLAB, and SURF facilities.
The SNO+ collaboration is operating a kilo-tonne scale liquid scintillator detector located at the SNOLAB underground facility in Sudbury, Canada. The major physics goal of the collaboration is to search for neutrinoless double beta decay with 130Te. A method has been developed to load tellurium into liquid scintillator so as to permit searches for neutrinoless double beta decay with high sensitivity. The approach involves the synthesis of an oil-soluble tellurium compound from telluric acid and an organic diol. The process utilises distillable chemicals that can be safely handled underground and affords low radioactive backgrounds, low optical absorption and high light yields at loading levels of at least several percent Te by weight.
The nEXO experiment is a planned five-tonne liquid xenon time projection chamber to search for the neutrinoless double beta decay of $^{136}$Xe with a projected half-life sensitivity of 1.35⨉10$^{28}$ years. To achieve optimal energy resolution in nEXO, charge and light signals must be reconstructed to sufficient precision. For charge signals, this requires accurately modelling and correcting for the effects of diffusion across the drift region; for light, the position-dependent photon transport efficiency must be well-calibrated. In this talk I will present efforts currently underway to address both of these aspects of energy reconstruction.
SNO+ is a kilo-tonne scale neutrino detector with the primary goal of searching for neutrinoless double beta decay in tellurium-130. The inner vessel of the SNO+ detector is currently filled with an organic liquid scintillator, which will be doped with the double beta isotope. While liquid scintillator detectors are ideal tools for neutrinoless double beta decay searches due to their exceptional mass scalability, good signal efficiency and low cost, their capability of reliable particle identification for active background rejection is often questioned. This poster will focus on new event reconstruction and particle identification techniques, their performance, and their use in SNO+ for enhancing the sensitivity to neutrinoless double beta decay as well as other physics searches.
KATRIN is probing the effective electron anti-neutrino mass by a precision measurement of the tritium beta-decay spectrum near the kinematic endpoint. Based on the first two measurement campaigns a world-leading upper limit of 0.8 eV (90% CL) was placed. New operational conditions for an improved signal-to-background ratio, the steady reduction of systematic uncertainties and a substantial increase in statistics allow us to expand this reach. Our poster displays the latest KATRIN results and provides insight into the neutral network approach used to perform the computationally challenging analysis. This work received funding from the European Research Council under the European Union Horizon 2020 research and innovation programme, and is supported by the Max Planck Computing and Data Facility, the Excellence Cluster ORIGINS, the ORIGINS Data Science Laboratory and the SFB1258.
PandaX-4T is a currently running experiment located at China Jinping Underground Laboratory searching for dark matter particles and studying the fundamental properties of neutrinos. It uses a liquid xenon TPC where neutrons and gammas from the liquid xenon container and PMT arrays significantly contribute to the total background. This poster presents the effort to build an active neutron and gamma veto surrounding the liquid xenon TPC. The 0.9 kton water shielding will first be instrumented with 8-inch PMTs forming a Cherenkov detector. To enhance the tagging efficiency, water-based liquid scintillator for which 5% liquid scintillator is mixed into the water using surfactants will be employed, with the possible addition of gadolinium. For its appreciable target mass, the detector will also detect cosmic rays and atmospheric neutrinos. For the next generation multi-ten-ton liquid xenon detector, the potential of using cold liquid scintillator as the veto detector medium will be explored.
136Xe nuclei capture electron neutrinos through charged-current (CC) interactions, leading to the excited states of 136Cs: (ν_e + 136Xe → e^- + 136Cs*). This process can be used for solar neutrino measurements and fermionic dark matter searches.
The recent observation of low-lying isomeric states in 136Cs* with lifetimes on the order of 100 ns [1] implies that the CC interaction can be identified by a delayed coincidence measurement. This technique involves detecting a prompt signal consisting of the electron and most of the de-excitation gamma rays, followed by a delayed signal consisting of the remaining de-excitation gamma rays with energies below 140 keV.
KamLAND-Zen is an experiment designed to search for the neutrinoless double beta decay of 136Xe, using an organic liquid scintillator that dissolves 750 kg of xenon gas (91% enriched in 136Xe). This presentation will discuss the feasibility of identifying the CC interaction in KamLAND-Zen.
References
[1] S.J. Haselschwardt et. al, arXiv:2301.11893 (2023).
Next generation neutrinoless double beta experiments aims at covering the inverted hierarchy region of the neutrino mass spectrum, with sensitivities on the half-lives greater than 10$^{27}$ years. The CUPID experiment will exploit cryogenic calorimeters to search for neutrinoless double beta decay of $^{100}$Mo. To reach the target sensitivities one of the key requirements is the control of the background level. In this talk I will detail the CUPID background sources and the background level estimation for each of them. The radioactive background expectations are based on Monte-Carlo simulations and material screening. Other backgrounds are derived from detector performances in R&D tests. Finally, I will show the expected sensitivity on the neutrinoless double beta decay half-live and the effective neutrino mass (depending on the Nuclear Matrix Element) based on the background predictions.
The Cryogenic Underground Observatory for Rare Events (CUORE) experiment is an ongoing search for neutrinoless double beta decay located at the Gran Sasso National Laboratory (LNGS) in Italy. Our previous work has shown that the quality of CUORE data can be improved with noise decorrelation algorithms using data from auxiliary devices including microphones, accelerometers, and seismometers. In this talk, I will discuss the implementation of these noise decorrelation algorithms in the CUORE analysis framework. I will showcase some results of the noise decorrelation including the impact on the energy resolution of the CUORE detector across multiple channels. I will also discuss how these denoising algorithms can be expanded to model non-linear systems and how these expansions improve the performance of the aforementioned noise decorrelation algorithms for the CUORE detector. Finally, I will discuss the fact that the CUORE detector is sensitive to vibrational noise from sea storms near LNGS in the Tyrrhenian and Adriatic seas and how we are able to demonstrate this using seismometric and geological data.
The Jiangmen Underground Neutrino Observatory (JUNO) is a multi-purpose physics underground experiment in southern China. Its central detector mainly consists of a 20-kton liquid scintillator and more than 17,000 20-inch photomultiplier tubes. A dedicated multi-messenger trigger system has been developed to maximize JUNO’s potential for astrophysics events, lowering the data-taking threshold down to O(10) keV equivalent. The currently existing calibration sources for JUNO are envisioned to be deployed to calibrate the MeV energy range, and hence new radioactive sources as well as calibration strategy are necessary to calibrate the sub-MeV range (O(10)~O(100) keV). For this purpose, Radium-226 (186 keV gamma-ray) and Americium-241 (59.5 keV gamma-ray) are considered as primary radioactive calibration sources. This poster will discuss the calibration feasibility in this very low-energy range including impacts on the calibration quality due to the source apparatus geometry, separation from Carbon-14 backgrounds, etc. using the JUNO detector simulation tool, and also present the status of the low-energy calibration source preparation.
The Jiangmen Underground Neutrino Observatory (JUNO) is a 20 kt liquid scintillator detector equipped with around 17,000 20-inch PMTs as well as 25,000 3-inch PMTs located 700 meters underground in southern China. It features a broad physics program with a primary goal of determining the neutrino mass ordering to 3σ in about 6 years. With an unprecedented energy resolution of 3%/$\sqrt{𝐸(MeV)}$, it will measure the spectrum of antineutrinos emitted from two nuclear power plants located 53 km from the detector. For the success of JUNO’s neutrino mass ordering determination and its oscillation parameter precision measurement program, a precise knowledge of the emitted reactor neutrino spectrum is crucial. Therefore, a satellite detector with 2.8 tons of gadolinium-doped liquid scintillator will be constructed in a distance of 30 m from one of the reactor cores to provide a precise measurement of the unoscillated spectrum with an energy resolution of less than 2%/$\sqrt{𝐸(MeV)}$.
This contribution will present studies on the sensitivity of the JUNO detector to determine the neutrino mass ordering in combination with its satellite detector TAO.
PMT waveform analysis is essential for high precision measurement of position and energy of incident particles in liquid scintillator (LS) detectors. JUNO is a next generation high precision neutrino experiment with a designed energy resolution of 3%@1MeV. The accuracy of the reconstruction of number of photo-electron (nPE) is one important key of achieving the best energy resolution. This poster introduces the machine learning-based nPE estimation methods. The calibration parameters of LS responses and PMT responses are used to generate training waveforms for supervised learning. Weakly supervised learning is applied to handle simulation errors. The photon counting performances of different methods will be presented.
The Jiangmen Underground Neutrino Observatory (JUNO) is the largest underground liquid scintillator experiment in the world, currently under construction in southern China. In its central detector, a 20-kton liquid scintillator in an acrylic vessel works as a neutrino target and is viewed by more than 17,000 20-inch photomultiplier tubes and more than 25,000 3-inch photomultiplier tubes. The primary experimental goal of JUNO is to determine the neutrino mass ordering by measuring the energy spectrum of reactor neutrinos. Vertex reconstruction and particle identification algorithms have been developed to suppress background contaminations in the reactor neutrino analysis sample as well as to understand the non-uniform energy response of the detector. Such algorithms can be developed with the radioactive neutron (Americium-Carbon) source which is planned to be regularly deployed to calibrate the JUNO detector responses. This poster will present the detailed methodology and reconstruction performances, especially on the vertex reconstruction and separation power between positron signals and alpha/fast-neutron backgrounds, using the JUNO detector simulation.
We present the concept and design of the P2 detector for measuring the temperature rise and scintillation light in a scintillating crystal at mK temperature. P2 is based on low temperature metallic magnetic calorimeters (MMCs) and it features both photon and phonon detectors structured on a single 3’’ Si wafer.
The photon sensor consists of a Nb superconducting stripline pickup coil enclosing about 50 Ag:Er paramagnetic sensor segments, each 300 nm thick and 450 µm long located on the central part of the Si wafer. This part is connected to the rest of the wafer through seven 100 µm long and 300 µm wide Si bridges structured using Si deep etching. In this way, the central part of the Si wafer acts as a photon absorber.
On the outer part of the wafer, three MMC channels based on the double meander design are located. Each of them is equipped with two Ag:Er sensors, but only one pixel is equipped with a gold cylinder. The three gold cylinders will be used both as thermal contact to the crystal and as mechanical support. We aim at demonstrating that the proposed detector design can achieve suitable performance for the AMoRE experiment.
In addition, we propose to investigate the use of the independent readout of the three MMC channels connected to the crystal for the identification of event position based on pulse shape analysis. The possibility to define a fiducial volume will be of utmost importance to reduce the contribution to the background due to surface events.
The CONUS experiment aims to detect coherent elastic neutrino nucleus scattering ($\mathrm{CE\nu NS}$). For this goal four $1\,\mathrm{kg}$ point-contact high-purity germanium detectors were operated near the $3.9\,\mathrm{GW_{th}}$ core of the Brokdorf nuclear power plant. A very good background suppression is crucial for the success of the experiment. Pulse shape discrimination (PSD) offers a tool to reduce the background by analyzing the shapes of the individual events. The interaction positions and number of interactions of the incoming particle within the diode have an impact on the pulse shape. Dedicated studies of this shape are therefore highly beneficial for the understanding and the rejection of background events near the detector surface. This talk presents the concept of the PSD for the CONUS experiment where a background suppression of (15-25)% is achieved. This will improve the sensitivity of future CONUS analyses and allow to further refine the background model in the sub-keV energy region.
The KATRIN collaboration aims to determine the effective electron anti-neutrino mass with a target sensitivity of $0.2\,$eV/c$^2$ ($90\,\%$ CL). To this end, KATRIN is currently performing high-statistics and high-resolution measurements of the tritium $\beta$-electron spectrum close to the endpoint region.
In addition to the neutrino mass search, the measured $\beta$-spectrum can be analysed for an imprint of sterile neutrinos in the eV mass range.
The signature of a sterile neutrino would be manifested as a kink-like distortion within the differential $\beta$-pectrum, where the kink position corresponds to the sterile mass and the amplitude to the active-to-sterile mixing.
This poster presents the analysis methods and current results of the light sterile neutrino search with KATRIN. Furthermore, an outlook on the expected sensitivity of additional measurement campaigns will be provided.
Future long-baseline experiments will be able to probe hitherto unexplored regions of sterile neutrino parameter space for masses ranging from meV to eV. We present an analytic calculation of the neutrino conversion probability $P(\nu_\mu \to \nu_e)$ in the presence of sterile neutrinos, with exact dependence on $\Delta m^2_{41}$ and matter effects. We further express the neutrino conversion probability as a sum of terms of the form $\sin(x)/x$, thus allowing a physical understanding of matter effects and their possible resonance-like behavior. We focus on the identification of sterile mass ordering (sign of $\Delta m^2_{41}$) at DUNE. The conversion probability obtained reveals the complex interplay between sterile and matter contributions. We perform numerical calculations of DUNE's sensitivity to sterile mass ordering over a broad range of sterile neutrino masses. Our analytic expressions enable us to explain the dependence of this sensitivity on $\Delta m^2_{41}$ values for all mass ordering combinations.
The Migdal effect predicts that the scatter of a neutral particle with a nucleus can result in atomic excitation or ionization. In liquid xenon dark matter detectors, the additional Migdal energy deposition enhances observable scintillation and ionization signals, and elevates a fraction of dark matter interactions from below the detector thresholds to above thresholds. Therefore, the Migdal effect can substantially enhance the sensitivity of existing experiments to interactions of sub-GeV mass dark matter candidates. We carried out a direct search for the Migdal effect in liquid xenon using O(10^5) xenon recoils in the keV region produced by scatters of 14.1MeV neutrons in a compact xenon time projection chamber. This data is predicted to contain thousands of Migdal interactions, of which a few hundred should produce observable signatures. We search for these signals in a way that is minimally impacted by uncertainties in nuclear cross section data or inaccuracies from modeling the detector response to nuclear recoils. The result of this search and the implications for dark matter experiments will be discussed.
Prepared by LLNL under Contract DE-AC52-07NA27344 (LLNL-ABS-848169).
The Migdal in Galactic Dark mAtter expLoration (MIGDAL) experiment aims to make the first direct and unambiguous observation of the Migdal effect from fast neutron scattering using intense DT and DD generators, allowing the effect to be investigated over a wide range of nuclear recoil energies.
The experiment uses an Optical Time Projection Chamber equipped with a stack of two glass-GEMs operating in 50-Torr CF4 based gas mixture, with light and change readout provided by a CMOS camera, a photomultiplier tube, and a 120 Indium-Tin-Oxide strip anode allowing precise three-dimensional reconstruction of the ionisation tracks from electron and nuclear recoils.
We will present preliminary results from the experiment’s commissioning using fast neutrons from the D-D generator at the Rutherford Appleton Laboratory's Neutron Irradiation Laboratory for Electronics (NILE).
The Windchime Project aims to utilize advancements in quantum sensing technologies to search for dark matter in the lab, based solely on its feeble gravitational interaction. Recent work has suggested the possibility to search for dark matter with mass near the Planck scale (around 10$^{19}$ GeV or 20 micrograms), a parameter space theoretically well-motivated and experimentally accessible. This presentation will introduce the concept of using an array of mechanical impulse sensors with a quantum-enhanced readout for dark matter detection, and its projected sensitivities. We will present the current status of the project, along with some preliminary results from recent computational efforts and a range of prototype setups in the collaboration.
The Windchime Project aims to search for ultraheavy dark matter ($m \sim 10^{19}\,\mathrm{GeV}$) by leveraging advancements in quantum sensing technology, striving to detect dark matter through its gravitational interaction alone. However, dark matter could instead exist as an ultralight bosonic particle ($m < \mathrm{eV}$), and it has recently been shown that the same technology could be used to detect dark matter in this ultralight regime. In this talk, we will show how an array of optomechanical sensors can be used to place leading bounds on ultralight dark photon dark matter. We will introduce the Windchime concept as it relates to measuring the wave-like signatures that such dark matter is expected to produce. Using this setup, we will demonstrate that Windchime will be sensitive to as-yet unprobed regions of the ultralight dark photon parameter space, surpassing the sensitivities of fifth-force experiments. Our results indicate that the Windchime experiment is set to be a powerful and versatile dark matter detector, tackling the dark matter puzzle from both mass extremes.
In this talk, I will introduce AION, a multi-stage atom interferometer project that aims to detect ultra-light dark matter candidates. The first stage, AION-10, will stand 10m tall in a stairwell in the Physics Department in the University of Oxford. AION-10 will operate in a gradiometer configuration, which means that two identical atom interferometers are run simultaneously, launching from the bottom and middle of the baseline. I will present near- and long-term sensitivity projections for several ultra-light dark matter candidates. I will also discuss potential backgrounds from anthropogenic and seismic noise, as well as possible mitigation strategies.
Potassium-40 ($^{40}$K) is a long-lived, naturally occurring radioactive isotope. It decays primarily by beta emission to calcium, and by electron-capture to an excited state of argon. An additional electron-capture to the ground state of argon theoretically exists, but has never been previously measured. Predicted intensities for this branch are highly variable (0-0.8%) and this decay channel impacts our understanding of nuclear structure and geochronological dating. Additionally, this decay acts as a challenging background for many rare-event searches, especially those involving NaI-based scintillators (ex. ANAIS-112, COSINE-100, COSINUS, DAMA/LIBRA, and SABRE) because of the 3 keV events produced from the electron capture that resides directly in their signal region. KDK (Potassium (K) Decay (DK)) is an international collaboration that has performed the first measurement of this branching ratio. The experiment is performed using a silicon drift detector with a thermally deposited, enriched $^{40}$K source inside the Modular Total Absorption Spectrometer (MTAS, Oak Ridge National Laboratory). MTAS is a large NaI detector whose high gamma-ray efficiency enables the proper discrimination between ground and excited state electron capture events. Our measurement yields a ground state branching ratio of 0.098% $\pm$ 0.023% (stat) $\pm$ 0.010% (syst). We report on the KDK experimental analysis and the extensive implications of our measurements.
In the Fall of 2019, the NEWS-G experiment used its latest detector, a 140 cm diameter Spherical Proportional Counter (SPC) to search for low-mass dark matter at the Laboratoire souterrain de Modane (LSM), in France. The detector has then been moved to SNOLAB in Canada, where it has been taking data since Fall 2022. SPCs are metallic spheres filled with gas, with a high voltage anode at the centre that attracts and amplifies ionization charges coming from atomic recoils. Having the sphere filled with pure methane, hydrogen was used as the target to produce new limits on the proton spin-dependent cross-section around masses of 1 GeV.
This talk will first introduce the NEWS-G experiment and describe the commissioning at the LSM with the shielding used, the SPC detection principle and the new multi-anode sensor. It will then focus on the calibrations using a UV laser and argon-37, as well as the background discrimination methods to remove alpha-induced events and spurious pulses coming from the electronics. Then, it will explain the profile likelihood ratio method that was used in order to derive constraints on WIMP mass and cross-section. Finally, it will describe the status of the recent data taken at SNOLAB and mention future projects.
The CRESST (Cryogenic Rare Event Search with Superconducting Thermometers) experiment operates cryogenic detectors in a a low-background setup at the deep underground facility of LNGS (Laboratori Nazionali del Gran Sasso) in Italy to search for nuclear recoils induced by dark matter particles. To collect the signal, a variety of target crystals such as CaWO$_4$, Al$_2$O$_3$, Si, and LiAlO$_2$ are equipped with transition edge sensors (TES). With detection thresholds for nuclear recoil down to 10 eV, CRESST-III is one of the leading experiments in the search for sub-GeV dark matter particles.
The ongoing CRESST-III measurement campaign is focused on investigating an excess of events above the level expected from known background sources observed at sub-keV energies (the so-called low energy excess), which limits the sensitivity of the experiment to low-mass dark matter. In this talk, we present the status of CRESST-III and report on the latest dark matter results, low energy excess studies, and prospects for precise sub-keV nuclear recoil calibration. We conclude the talk with our future plans and prospects.
The latest results from the DEAP-3600 experiment will be presented. Located 2 km underground at SNOLAB in Sudbury, Canada, DEAP-3600 is looking to detect dark matter using 3.3 tonnes of liquid argon contained in a large ultralow-background acrylic cryostat that is instrumented with 255 photomultiplier tubes. Key to this experiment is the excellent demonstrated performance of pulse-shape discrimination against low-energy beta decays, as well as position reconstruction and other background rejection techniques against alpha decays and neutron scatters. The broad physics programme of DEAP-3600, with measurements and searches for new physics will be discussed, as well as the status of detector upgrades in progress.
The PICO collaboration is currently commissioning the PICO-40L bubble chamber for use in dark matter direct detection. PICO-40L is the first large-scale implementation of the so-called “Right-Side-Up” design which inverts the detector geometry compared to previous bubble chambers. This orientation is intended to reduce the possibility of spurious backgrounds and improve upon the world-leading spin dependent WIMP-proton limit set by PICO-60. This detector also serves as a proof-of-concept for the next-generation PICO-500 detector, which is currently in the procurement phase.
The status and first results from PICO-40L will be presented.
The direct detection of light (sub-MeV) dark matter presents a significant challenge due to the need for very low energy thresholds. I will discuss the Optomechanical Dark-matter INstrument (ODIN), a new proposal to use a superfluid helium optomechanical cavity to search for dark matter in the keV mass range. Scattering dark matter excites a single (ueV range) phonon in the superfluid helium, which is then converted into an (eV range) photon via an optomechanical interaction with a pump laser. This photon can be efficiently detected, providing a means to sensitively probe keV scale dark matter. Optomechanical systems have demonstrated sensitivity to phonons with ueV energies, making them ideally suited to the detection of light dark matter.
Quantum devices with ultrahigh sensitivities are being designed for various purposes ranging from developing quantum computers to building powerful telescopes. Typically, they use the sharp transition between superconducting and normal states of matter to detect small energy deposition. Such devices have also been used in direct detection experiments for light dark matter. I will talk about a new way of looking for dark matter signals using power measurements in these devices. I will describe how new constraints are set in the mass range 1 MeV to 10 GeV for galactic halo dark matter, as well as for thermalized dark matter near the Earth’s surface that can arise in strongly interacting models.
Direct searches of sub-GeV light dark matter and its interactions with electrons has been a fast-progressing area. Because the observable energies overlap with typical atomic, molecular, or condensed-matter scales, the detector responses play a crucial role in experimental data analyses and interpretation (so far, in terms of exclusion limits).
In this talk, I will discuss our approach in obtaining atomic response functions based on well-benchmarked many-body methods, and its comparison with other atomic approaches. Our progress of compiling an atomic response function database for general use will also be reported.
Utilising data from the direct detections of compact binary coalescences (CBCs) in the first three observing runs of the LIGO-Virgo-KAGRA Collaboration (LVK), we estimate the redshift dependence of the binary black hole (BBH) population. Specifically, we search for signs that the mass distribution of BBHs varies over cosmic history. The detection of such variation would allow us to gain more knowledge about the population itself, but also the formation channels of CBCs throughout the Universe. However, current CBCs took place at low to moderate redshift, limiting our ability to constrain the high redshift behaviour of the quantities of interest. Nevertheless, current upper limits on the gravitational-wave background (GWB) from CBCs can be used as an additional source of information to uncover the high redshift behavior of the merger rate and the mass distribution. We implement this joint CBC and GWB analysis in a Bayesian framework, allowing us to construct posteriors for the parameters describing the population of CBCs and their evolution with redshift.
Current parameter estimation techniques for coalescence of compact binaries assume just one event in the data stream. With the low detection rate of current interferometers, it has not been a problem so far, as overlapping signals are highly improbable. This will change with the next generation (3G) of detectors, like Cosmic Explorer and Einstein Telescope, with hundreds of overlaps per year. Previous work has shown that not accounting for them can lead to bias in parameter estimation.
In our work we tackle this problem by performing joint parameter estimation – modeling multiple sources in the data at once. Previously, this technique was too computationally expensive to use with long duration signals expected in 3G detectors , but we have combined it with likelihood approximation known as relative binning , making the analysis feasible. For comparison, we also perform hierarchical subtraction, where we model one signal at a time, subtract it from data and analyze again.
We consider different classes of overlapping signal scenarios like two binary black hole signals, two neutron star signals, and three overlapping signals. Using the joint parameter estimation we are able to accurately estimate the parameters, mitigating the bias observed when we model just one signal at a time.
Many gravitational-wave events from mergers of binary stars consisting of black holes and neutron stars have been observed, while gravitational waves from supernovae have not been observed yet.
Investigating temporal changes in the frequency and amplitude of gravitational waves is important for studying the physics of gravitational wave sources. For time-frequency analysis of gravitational waves both from mergers and supernovae, we are proposing to use the Hilbert-Huang transform (HHT), which comprises empirical mode decomposition (EMD) followed by Hilbert spectrum analysis. An essential aspect of the EMD involves the generation of envelopes through interpolating extrema values. The original EMD utilizes cubic spline interpolation, but it occasionally becomes unstable and it will reduce performance of the EMD.
Now we propose extended versions of the HHT, including substituting Akima spline interpolation for the cubic spline and careful treatment near both ends of time series data. In addition, the code was parallelized using MPI to reduce computation time.
In this talk, we will show the results of comparing the original HHT and the proposed HHT.
The dawn of gravitational-wave (GW) astronomy in the last decade has propelled our understanding of many areas of astrophysics. Most notably, GW170817, the first binary neutron star merger observed in both GWs and electromagnetic (EM) waves, kickstarted the age of multi-messenger GW astronomy. With the onset of the LVK Collaboration's O4 and upcoming EM instruments, multi-messenger astrophysics has never so promising. I will review recent searches and results for multi-messenger counterparts to GW events, and describe challenges and prospects for future observations.
The Astrophysical Multimessenger Observatory Network (AMON) aims to connect the world's leading high-energy and multimessenger observatories. AMON looks to evoke the discovery of new multimessenger phenomena, exploit these phenomena as tools for fundamental physics and astrophysics, and explore for multimessenger activity in archival datasets. Here we present a summary of the current activities of AMON and the future plans: AMON is currently distributing low-latency multimessenger alerts from the Neutrino-Electromagnetic (NuEM) channel, and helping in the propagation of trigger alerts from observatories such as IceCube and HAWC. AMON will also continue providing useful real-time analyses of a wide variety of high-energy and multimessenger data streams including gravitational waves from the O4 run from the LIGO-Virgo-Kagra collaboration; strengthening its ties with the theoretical and time domain astrophysics communities; and looking for new analysis methods to perform Multimessenger searches such as machine learning.
Core Collapse supernovae are among the most interesting source of possible multimessenger detections, given the joint production of electromagnetic, neutrino and gravitational waves (GW). In this work we investigate the correlation of SASI structure of neutrino and GW to enhance the GW detection. We compare different search analyses for the case of a benchmark three-dimensional CCSN simulation with zero-age main sequence mass of 24 solar masses. In particular, we build a matched filter analysis which increase detection efficiency of 30% with respect to a standard excess power algorithm for nearby CCSN (less than 1.5 kpc). At further distance we expect that additional work is needed to outline the best strategy for GW detection from CCSN.
The Telescope Array is a hybrid cosmic ray detector utilizing both batteries of fluorescence telescopes and a large array of scintillator surface detectors to measure the properties of extensive air showers initiated by ultra high energy cosmic rays when they enter the Earth's atmosphere. Located in central Utah, USA, the Telescope Array is the largest cosmic ray detector in the northern hemisphere. Following evidence of a hot spot in the arrival direction of ultra high energy cosmic rays, the Telescope Array is presently expanding from 700 sq km to 2800 sq km. The status of spectral, composition, and source search measurements will be presented in addition to an update on the deployment of the TAx4 detectors.
AugerPrime, the upgrade of the Pierre Auger Observatory, is nearing completion and the Observatory is now prepared to collect physics data after the commissioning of the new components. The Pierre Auger Observatory has demonstrated, based on the data collected thus far, the existence of the cutoff in the spectrum with high accuracy. However, the origin of this cutoff remains incompletely understood. The upgraded Observatory is designed to address the unresolved questions regarding the nature of the cosmic ray flux cutoff thanks to its capability to disentangle the muon and electromagnetic components of extensive air showers. Furthermore, the measurement of the muon component at ground level can verify the accuracy of hadronic interaction models currently used.
This presentation will provide an overview of the status of the Observatory and the accurate commissioning done before the start of the physics run. Furthermore, we will present the initial data from Phase 2 data mainly dedicated to proving the continuity of operation of the Observatory from Phase 1 to Phase 2.
Measurements of anisotropic arrival directions for ultra-high-energy cosmic rays provide important information for identifying their sources. On large scales, cosmic rays with energies above 8 EeV reveal a dipolar flux modulation in right ascension with a significance of more than $5 \sigma$, with the dipole direction pointing 125° away from the Galactic center. This observation is explained by extragalactic origins. Also, model-independent searches for small- and intermediate-scale overdensities have been performed in order to unveil astrophysically interesting regions. On these scales, no significant features could be detected. However, intermediate-scale analyses comparing the measured arrival directions with potential source catalogs show indications for a coincidence of the measured arrival directions with catalogs of starburst galaxies and the Centaurus A region.
In this contribution, an overview of the studies regarding anisotropies of the arrival directions of ultra-high-energy cosmic rays measured at the Pierre Auger Observatory on different angular scales is presented and the current results are discussed.
One of the major unresolved issues in cosmic-ray physics is the transition from galactic to extra-galactic cosmic rays. However, constraints can be obtained by studying the cosmic ray anisotropy in the energy range from PeV to EeV where the transition is expected to occur. The sensitivity to cosmic-ray anisotropy is in particular a matter of statistics. With the upcoming IceCube-Gen2 surface array, which will cover 8 times more area than the existing IceTop surface array, there will be an increase in statistics and capability to investigate cosmic ray anisotropy with higher sensitivity. We will present a simulation study of the sensitivity to the cosmic-ray anisotropy signal expected with the IceCube-Gen2 surface array.
With the implementation of a low-energy trigger, the surface array of the IceCube Neutrino Observatory is able to record cosmic-ray induced air showers with a primary energy of just a few hundred TeV. This extension of the energy range closes the gap between direct and indirect observations of primary cosmic rays and provides the potential to test the validity of hadronic interaction models in the sub-PeV regime. Composition analyses at IceCube highly benefit from its multi-detector design. Combining the measurement of the electromagnetic shower component and low-energy muons at the surface with the response of the in-ice array to the associated high-energy muons improves the reconstruction accuracy and opens new possibilities to extract the primary particle's mass.
In this talk, a new methodical approach for the analysis is presented, including techniques for the identification of coincident background in the in-ice detector and a machine learning model based on convolutional neural networks to determine the elemental composition. The achieved performance in reconstructing the primary mass and energy of air shower events is discussed.
The ANTARES neutrino telescope operated in the Mediterranean Sea from 2006 to 2022. The detector array, consisting of photomultipliers encompassing a volume of 0.01 km3, was designed to detect high-energy neutrinos covering energies from a few hundred GeV up to the PeV range. Despite the relatively small size of the detector, the results obtained are relevant in the field of neutrino astronomy, including hints of cosmic neutrino signals.
This presentation will provide an overview of those results and the lessons learned from the operation of the detector.
MicroBooNE is an 85-tonne active mass liquid argon time projection chamber (LArTPC) at Fermilab. With an excellent calorimetric, spatial and energy resolution, the detector was exposed to two neutrino beams between 2015 and 2020. These characteristics make MicroBooNE a powerful detector not just to explore neutrino physics, but also for Beyond the Standard Model (BSM) physics. Recently, MicroBooNE has published a search for heavy neutral leptons and Higgs portal scalars from kaon decays. In addition, MicroBooNE has developed tools for a neutron-antineutron oscillation search for the upcoming Deep Underground Neutrino Experiment (DUNE). This talk will explore MicroBooNE’s capabilities for BSM physics and highlight its most recent results.
ArgoNeuT was a 0.24-ton Liquid Argon Time Projection Chamber (LArTPC) neutrino detector at Fermilab running from 2009 to 2010. It was located along the NuMI neutrino beam upstream of the MINOS near detector and collected six months of data in anti-neutrino beam mode. ArgoNeuT’s dataset has been used to perform numerous first neutrino cross-section measurements on argon. It can also be used to probe physics beyond the standard model resulting from high-energy proton fixed-target collisions in the NuMI beam. ArgoNeuT has recently performed the first search for heavy QCD axions in a LArTPC neutrino detector. These could be produced in the NuMI beam target and absorber as a result of meson-mixing and then decay with a dimuon signature that can be identified using the unique capabilities of ArgoNeuT and the MINOS near detector. This decay channel is motivated by a broad class of heavy QCD axion models that address the strong CP and axion quality problems with axion masses above the dimuon threshold. This talk will present the results of this search and the new constraints that can be applied on the heavy QCD axion parameter space.
The detection of the Diffuse Supernova Neutrino Background (DSNB) flux will provide invaluable insights into constraining cosmological models, core-collapse dynamics and neutrino properties. The Super-Kamiokande Gd (SK-Gd) experiment currently exhibits the best sensitivity for discovery due to enhanced neutron tagging capability with 0.01% gadolinium sulphate loading, as per this analysis. While the IBD coincidence signature significantly reduces backgrounds, the signal region remains dominated by cosmic muon spallation and atmospheric neutrinos. This study explores a novel approach to background reduction by leveraging topological features of SK events with the discriminative power of convolutional neural networks (CNNs). Well-established techniques for data pre-processing, event selection and feature extraction are applied to effectively train a CNN model on SK DSNB and atmospheric Neutral Current (NC) events. Preliminary performance of the CNN model shown in this presentation highlights the potential of machine learning techniques to outperform traditional methods and significantly improve the DSNB signal efficiency.
Future ktonne-scale, scintillation-based neutrino detectors, such as THEIA, plan to exploit new and yet to be developed technologies to simultaneously measure Cherenkov and scintillation signals in order to provide a rich and broad physics program. These hybrid detectors will be based on fast timing photodetectors, novel target materials, such as water-based liquid scintillator (WbLS), and spectral sorting. Besides an overview on THEIA’s program for low energy astroparticle and particle physics this talk also gives an overview on a currently realized demonstrator experiment, called EOS. This novel detector with an approximately 4-tonne target fiducial volume is under construction at the UC Berkeley and LBNL (Lawrence Berkeley National Laboratory). The detector will provide a test-bed for these emerging technologies required for hybrid Cherenkov/Scintillation detectors. Furthermore, EOS will deploy calibration sources to verify the optical models of WbLS and other liquid scintillators with slow light emission, to enable an extrapolation to ktonne-scale detectors. This input will support the development of advanced techniques for reconstructing event energy, position, and direction in hybrid detectors significantly. After achieving these goals, EOS can be moved near a nuclear reactor or in a particle test-beam to demonstrate neutrino event reconstruction or detailed event characterization within these novel detectors.
The RES-NOVA project will hunt neutrinos from core-collapse supernovae (SN) via coherent elastic neutrino-nucleus scattering (CEνNS) using an array of archaeological lead (Pb) based cryogenic detectors. The high CEνNS cross-section on Pb and the ultra-high radiopurity of archaeological Pb enable the operation of a highly sensitive neutrino observatory, equally sensitive to all neutrino flavors, with dimensions at the cm-scale. The first phase of the RES-NOVA project is planning to operate a demonstrator detector with a total active volume of (30 cm)$^3$. It will be sensitive to SN bursts from the entire Milky Way Galaxy with >3σ sensitivity, while running PbWO$_4$ detectors with 1 keV energy threshold. RES-NOVA will discriminate core-collapse SNe from black-holes forming collapses with no ambiguity even with such small volume detector. The main SN parameters can potentially be constrained with a precision of few % while looking at $\nu_{\mu/\tau}/\overline{\nu}_{\mu/\tau}$. We will present the performance of the first prototype detectors, and sensitivity projections for the full detector. We will show that RES-NOVA has the potential to lay the foundations for a new generation of neutrino observatories, while relying on a very simple and modular experimental setup.
The Jiangmen Underground Neutrino Observatory (JUNO) is a 20 kton multipurpose liquid scintillator (LS) detector currently under construction in southern China. One of the capabilities of JUNO detector is to search for the baryon number violation processes, which would be a crucial step towards testing the GUT and explaining the matter-antimatter asymmetry of the Universe. The nucleon decay provides a direct observation of baryon number violation and has been the focus of many experiments over the past several decades. The large LS detector of JUNO has a distinct advantage in detecting nucleon decay. The JUNO LS target consists of about 88% $^{12}$C and 12% $^{1}$H. The invisible decays of neutrons from the s-shell in $^{12}$C will result in a highly excited residual nucleus. It has been found that some de-excitation modes of the excited nucleus can produce time- and space-correlated triple signals. This talk (poster) reports the JUNO sensitivity to search for invisible decay modes of the neutron. Based on MC simulations, it made comprehensive estimates for all possible backgrounds,including coincidences from inverse beta decays, natural radioactivities and cosmogenic isotopes. The correlated backgrounds from atmospheric neutrino neutral current events have also been evaluated. We adopt the Pulse Shape Discrimination (PSD) and Multi-Variate-Analysis (MVA) techniques for suppressing backgrounds. A preliminary sensitivity to neutron invisible decays at JUNO will be presented.
KM3NeT is a cubic kilometer neutrino underwater telescope which is located in the Mediterranean Sea. The commissioning of the detector infrastructure is currently underway. The Cherenkov Telescope Array (CTA) is the next generation ground-based observatory for gamma-ray astronomy at very high energies. Both collaborations contributed to ESCAPE, the European Science Cluster of Astronomy and Particle Physics, which brings together many astrophysics and particle physics experiments to further open science in the community via the European Open Science Cloud (EOSC). The data being of the event type for both neutrino and gamma astronomy experiments suggest using the same scientific tools for analyses. In the multi-messenger era, synergies of different experiments for investigating a specific scientific question yields significant additional insights not achievable with information from one messenger alone. This approach was successfully employed in a combination of KM3NeT and CTA data to distinguish between leptonic and hadronic emission scenarios of gamma-ray sources in the Milky Way using a common software framework. This contribution demonstrates the successful deployment of the analysis into the ESCAPE EOSC thematic cluster infrastructure for future usage in the open science regime.
The KArlsruhe TRItium Neutrino experiment (KATRIN) is searching for the signature of the neutrino mass in the endpoint region of the tritium beta-decay spectrum. KATRIN combines a high-intensity gaseous molecular tritium source with a high-resolution spectroscopy using electrostatic filter with magnetic adiabatic collimation. This technique allowed KATRIN to reach with the first 5% of the data a sub-eV sensitvity to the neutrino mass and to set an upper limit of 0.8 eV$/c^2$ (90% CL).
In this talk an overview of the KATRIN experiment is presented. The analysis of the new dataset of KATRIN with 6 times increased statistics and further improvements in terms of signal-to-background ratio and systematics is discussed. The talk closes with an outlook on the future prospects of KATRIN.
The goal of the Project 8 experiment is to measure the absolute neutrino mass using tritium beta decay and Cyclotron Radiation Emission Spectroscopy (CRES) with a design sensitivity to the neutrino mass of 40 meV. CRES is a method for performing precision electron spectroscopy that was first demonstrated by Project 8. In the work presented here, we performed the first measurement of the tritium beta-spectrum endpoint using CRES, and we used that background-free spectrum to place a limit on the absolute neutrino mass. This new measurement provides critical information on the techniques necessary to extend the reach of Project 8 towards its design goal such as determining the detection efficiency and measuring the instrumental resolution. In this talk I will present the recent results from Project 8 and discuss the important advances made in performing a CRES experiment with low background and high resolution.
This work is supported by the US DOE Office of Nuclear Physics, the US NSF, the PRISMA+ Cluster of Excellence at the University of Mainz, and internal investments at all collaborating institutions.
The NEXT experiment aims at the sensitive search of the neutrinoless double beta decay ($\beta\beta0\nu$) in $^{136}$Xe, using high-pressure gas electroluminescent time projection chambers. The NEXT-White detector, a radiopure demonstrator operated in the Laboratorio Subterraneo de Canfranc (LSC), has been used to implement the first searches with this technology. The analysis considers the combination of 271.6 days of $^{136}$Xe-enriched data and 208.9 days of $^{136}$Xe-depleted data. Limits to the half-life of the $\beta\beta0\nu$ decay are obtained with both a background-model-dependent approach and a novel direct background-subtraction technique. With a fiducial mass of only 3.50$\pm$0.01 kg of $^{136}$Xe, 90\% C.L. lower limits are found in the $T_{1/2}^{0\nu}>5.5\times10^{23}-1.3\times10^{24}$ yr range, depending on the method. The presented techniques will be fully exploited with larger NEXT detectors. The NEXT-100 detector, holding up to $\sim$100 kg of Xe, is currently being installed in the LSC. With a background index below 5$\times$10$^{-4}$ counts/keV/kg/year, this detector has an expected sensitivity of 6$\times$10$^{25}$ yr after 3 years of data taking. NEXT-100 will also set the grounds for the construction of a ton-scale detector, NEXT-HD, boosting the sensitivity above 10$^{27}$ yr. An extensive R&D line is being conducted to equip NEXT-HD with Ba-tagging capabilities, so a truly background-free experiment can be eventually implemented.
SuperNEMO is searching for the hypothesised lepton-number-violating process, neutrinoless double-beta decay (0νββ). Extending NEMO-3’s world-leading design, our isotope-agnostic tracker-calorimeter architecture has the unique ability to track trajectories and energies of individual particles. This is a vital background-rejection tool, and enables detailed studies of the Standard Model double-beta decay process (2νββ) that produces two electrons, invisible neutrinos and, for some nuclear transitions, photons. By studying the electrons’ and photons’ energies and the angles between their trajectories at the emission point, SuperNEMO will be able to investigate nuclear processes indistinguishable to other technologies. For example, we can study decays to excited nuclear states, and provide constraints on the axial coupling constant, g_A. Precise measurement of the observables of 2νββ decays allows searches for beyond-the-Standard-Model effects like exotic 0νββ modes, Lorentz-violating decays and bosonic neutrino processes.
The SuperNEMO Demonstrator at LSM, France is now taking data with the full tracker and calorimeter from a 6.3kg Se-82 double-beta source. We are currently calibrating the detector with an automatic Bi-207 source deployment system, as well as taking the vital background data required to isolate our future signal samples. A multi-layer shielding system, now under construction, will allow us to start collecting double-beta-decay data later this year.
AMoRE is an international experimental project to search for the neutrinoless double beta ($0\nu\beta\beta$) decay of $^{100}$Mo utilizing enriched molybdate scintillating crystals and metallic magnetic calorimeters in a mK-scale cryogenic system. The project aims for zero background in the region of interest near 3.034 MeV, the Q-value of $^{100}$Mo $0\nu\beta\beta$ decay, by simultaneously measuring phonon and photon signals for high energy resolution and good rejection of alpha-induced backgrounds. AMoRE-I, a phase following the completed AMoRE-pilot, operates with thirteen $^{48depleted}$Ca$^{100}$MoO$_4$ and five Li$_2$$^{100}$MoO$_4$ crystals in the Yangyang underground laboratory. Since the beginning of the experiment in Sep. 2020, we have accumulated more than 600 days of stable physics data with advanced noise suppression, lowering the background level below the pilot phase. With an improved ROI estimation analysis method and cut efficiency calculation, we will report a new higher half-life limit of $^{100}$Mo $0\nu\beta\beta$ decay from the AMoRE-I experiment data.
BINGO is a project dedicated to explore new methods for background reduction in experiments searching for $0\nu2\beta$ decay. It is based on bolometers, one of the most promising techniques to search for $0\nu2\beta$.
BINGO technology aims at reducing the background index down to $10^{-5}$~counts/(keV kg yr) in the region of interest, thus boosting the sensitivity on the effective Majorana neutrino mass. This can be achieved by: (i) having a revolutionary detector assembly with a reduction of the passive materials facing the detector; (ii) increasing the light detector sensitivity thanks to Neganov-Luke amplification; (iii) using a cryogenic active shield, based on BGO scintillators with bolometric light detector readout surrounding the experimental volume. In this talk we will describe all the innovative approaches and the most recent results of the prototype tests will be present as well.
Low background germanium detectors with excellent energy resolution are advantageous to search for $^{76}$Ge neutrinoless double beta decay process. We proposed an experimental program, CDEX-300$\nu$, using $^{76}$Ge enriched broad energy germanium detectors at China Jinping Underground Laboratory (CJPL). In this talk, I will focus on the preconceptual design and plan of the CDEX-300$\nu$. The preliminary R&D progress of detectors, electronics and low background techniques will also be introduced.
A solid observation of neutrino-less double beta decay (0νDBD) relies on the possibility of operating high-energy resolution detectors with detailed background control. Scintillating cryogenic calorimeters are one of the most promising tools to fulfill the requirements for a next-generation experiment. CUPID-0 has been the first demonstrator of the proposed CUPID experiment based on this experimental technique. The detector, consisting of 24 enriched and 2 natural ZnSe crystals, has been taking data at Laboratori Nazionali del Gran Sasso from March 2017 to December 2018 (Phase I) and from May 2019 to February 2020 (Phase II), for a total exposure of 16.59 kg yr of ZnSe. In this contribution, we present the final results of CUPID-0 phase-I and phase-II combined background model. We identify
with improved precision the background sources in the region of interest for neutrinoless double β-decay, making more solid the foundations for the background budget of the next-generation CUPID
experiment. Relying on the excellent data reconstruction, we measure the two-neutrino double β-decay half-life of $^{82}$Se with unprecedented accuracy.
The $4.8\sigma$ low-energy excess (LEE) of electron-like events observed by MiniBooNE is one of the longest-standing anomalies in particle physics. As the MiniBooNE reconstruction relied on the identification of Cherenkov rings, the excess could come from extra electrons or photons in the detector. This talk covers new developments regarding each hypothesis. The MicroBooNE experiment has recently constrained the level to which excess $\nu_e$ interactions from the Booster Neutrino Beam can explain the LEE. We show that the MicroBooNE constraints are significantly alleviated if the LEE comes from $\overline{\nu}_e$ rather than $\nu_e$ interactions. This effect is due to a difference in the low-energy suppression of $\overline{\nu}_e$ and $\nu_e$ cross sections in carbon v.s. argon. Next, we discuss a model comprised of an eV-scale sterile neutrino and a heavy neutral lepton $\mathcal{N}$ with a transition magnetic moment coupling to active neutrinos, also known as a "neutrissimo". It is shown that the visible decay $\mathcal{N} \to \nu \gamma$ can explain the bulk of the energy and angular distributions of the LEE. New constraints on the neutrissimo model are also derived from MINER$\nu$A neutrino electron elastic scattering measurements. While they do not currently rule out the MiniBooNE solution, a dedicated MINER$\nu$A analysis would likely be sensitive to the MiniBooNE-preferred region of neutrissimo parameter space.
Recently, there has been an increased interest in studying the
manifestations of the wave packet (WP) nature of neutrinos in neutrino
oscillations experiments. In particular, a number of papers the
possibilities of probing quantum decoherence due to separation of
neutrino WPs and the corresponding damping of neutrino oscillations in
reactor and neutrino source experiments were discussed. It has been also argued that such decoherence effects may reconcile the results of the BEST neutrino source experiment with reactor neutrino data. I will report the results of our recent work (arXiv:2208.03736), in which we
studied in detail damping of neutrino oscillations in these two types of experiments. We have demonstrated that the effects of decoherence by WP separation can always be incorporated into a modification of the energy resolution function of the detector and so are intimately entangled with it. We also estimated, for the first time, the lengths of WPs of reactor neutrinos and of neutrinos from $^{51}$Cr source. Our conclusion is that the effects of finite neutrino WP lengths are many orders of magnitude below the current experimental sensitivities and so they cannot be probed in reactor and source experiments.
We present an analysis of neutrinoless double beta decay (DBD) mediated by non-interfering exchange of light and heavy neutrinos, in the context of current calculations of nuclear matrix elements (NME) in different nuclear models.
We derive joint upper bounds on the light and heavy contributions to the Majorana effective mass through an updated combination of the latest data from the following experiments and isotopes: GERDA and MAJORANA (Ge), KamLAND-Zen and EXO (Xe), and CUORE (Te), for different choices of NME. We then consider three Ton-scale project which might provide possible DBD evidence at >3sigma level in the allowed parameter space: LEGEND (Ge), nEXO (Xe) and CUPID (Mo). The combinations of possible DBD signals mediated by light, heavy, and light+heavy neutrinos is studied for different choices of NME, showing the conditions under which the underlying mechanism(s) can be identified or not. In particular, the role of NME ratios in different isotopes is elucidated through appropriate graphical representations. By using different "true" and "test" NME sets as a proxy for NME uncertainties, significant bias effects may emerge, confusing the identification of light vs heavy neutrino contributions to DBD signals. These results provide further motivations for more accurate NME calculations and for multi-isotope DBD searches at the Ton scale.
After the first observation of coherent elastic neutrino-nucleus scattering (CE$\nu$NS), the question arises how to further exploit this signal for a wide variety of future investigations. In this context, nuclear reactors with their intense emission of low-energy antineutrinos in combination with high-purity germanium detectors have already shown their potential for CE$\nu$NS studies and represent a scalable technology for future precision experiments. Measurements such as those performed by the CONUS collaboration are of interest since deviations from the Standard Model CE$\nu$NS prediction could indicate the existence of new neutrino interactions. In particular, a light vector boson may imply corrections to the Weinberg angle, so increasing the precision of this observable will help to probe additional U(1) extensions of the Standard Model. In this talk, we discuss the potential of future germanium-based reactor experiments for precision measurements. Using a data-based reactor antineutrino prediction, we present the experimental sensitivity to the weak mixing angle and the parameters of generic light vector models. In addition, the effects of characteristic experimental parameters such as detector mass and energy threshold are presented and it is shown where improvements in detector design could have the strongest impact on physics investigations. Finally, we flesh out our results by showing the potential of the recently announced follow-up experiment CONUS+.
The process of Coherent Elastic Neutrino-Nucleus Scattering (CEvNS), first observed in 2017 by the COHERENT collaboration, has provided a powerful tool to study new physics scenarios within the neutrino sector. In this talk, we focus on the Non-Standard Interactions (NSI) formalism, and we present the current bounds on NSI flavor changing and non-universal parameters using CEvNS. Our analysis include data from the two measurements provided by COHERENT using cesium iodide and liquid argon detectors. In addition, we present the sensitivities that can be expected from different detection technologies in future facilities such as the proposed European Spallation Source.
Newly-developed Skipper-CCDs are a promising technology to detect neutrinos scattering with Silicon nuclei by exploiting the CEvNS channel. Their ultra-low read-out noise allows for an unprecedented sensitivity to interactions with energy transfers in the eV region. We report results from the first Skipper-CCD sensor installed inside the containment building of the Atucha-II nuclear power plant, a 2 GWth commercial nuclear reactor in Argentina; the detector is deployed 12 m from the reactor core. In this work, we discuss the commissioning of the sensor, assess its current performance, and discuss its sensitivity for rare event detection.
The recent detection of coherent elastic neutrino-nucleus scattering (CEνNS) creates the possibility to use neutrinos to explore physics beyond standard model, with small-size detectors. However, the CEνNS process generates signals at the few keV level, requiring very sensitive detector technologies. The European Spallation Source (ESS) has been identified as an optimal source of low energy neutrinos, offering an opportunity for a definitive exploration of all phenomenological applications of CEνNS.
A number of different detector approaches are currently under development for deployment at ESS. These next-generation technologies will be able to observe the process with lower energy threshold and better energy resolution than current detectors. The combination of their observations will allow for a complete phenomenological exploitation of the CEνNS signal. In particular, these measurements will not be statistically-limited, a result of the large neutrino flux expected at the ESS.
In this talk I will present the main projects currently being developed to detect the CEνNS at the ESS, with a strong focus on two of them: the GanESS project which will use high pressure gas TPC filled with different noble gases; and the CoSI project, which employs cryogenic undoped CsI crystals.
Considering that, low-energy nuclear recoils induced by elastic neutrino nuclear coherent scattering with nuclei in pure materials have become an important, active area in particle physics, we present a detailed model to compute silicon ionization efficiency (quenching factor) based on Lindhrad's integral equation, explaining the details considered to match recent low-energy published data. Where we will show the effect of applying this quenching factor to a CE$\nu$NS like rate, comparing the neutrino spectrum from other quenching factor curves that have been used in recent experiments. We are going to show the universality applicability of this model to other materials like noble liquids TPC detectors, which in recent years have become relevant for neutrino low energy CE$\nu$NS searches. Furthermore, we are going to present and discuss a study of effects that account in a direct way for the ionization efficiency, especially at low energies, which means the energy conversion of eV_{nr} to eV_{ee}.
The Pierre Auger Observatory has implemented a novel method of astroparticle detection that combines various techniques and has an open data policy. The dissemination of information about the different astroparticle detection methods, ranging from surface water Cherenkov detectors to underground scintillator detectors, is now possible due to access to specialized tools for data analysis. This allows for the introduction of the topic of astroparticles to teachers and students at different educational levels. This marks a significant moment for the Observatory. In this presentation, we will discuss the diverse outreach initiatives undertaken by the Observatory, which have facilitated interaction among members of the international collaboration and enabled collaborative actions between the permanent staff of the Observatory in Malargüe and other institutions worldwide through synchronous meetings. These programs provide visitors with the opportunity to explore the environment of secondary particle cascades produced by cosmic rays, leading to a record number of monthly visitors since the opening of the Observatory 25 years ago.
Communication can be defined, among other things, as interactions that occur between two or more individuals. To communicate abstract concepts such as dark matter, we sought new and creative ways of engaging with diverse communities through the exploration of senses (gastronomy or art) and recreational activities (game play or design items). In this presentation, we will share specific experiences, such as creating a dark matter ice cream and collaborating with local design entrepreneurs. We will also discuss the successes and challenges that arose during this search for innovative forms of engagement
We present the result of a cross-disciplinary collaboration between Donald Fortescue of the California College of the Arts in San Francisco and researchers from the KM3NeT Collaboration. The project continues the successful art/science research collaboration between Fortescue and Gwenhaël De Wasseige, initiated during Fortescue’s US National Science Foundation funded residency with IceCube at the South Pole in the austral summer of 2016/17.
Fortescue created an analog sound producing instrument which was installed within a standard KM3NeT spherical glass DOM. This instrument, titled “Bathysphere”, was deployed in the sea for the first time adjacent to the ORCA array of KM3NeT off the coast of France on September 23, 2021.
The video work “Below the Surface” incorporates sound and video recorded from within the “Bathysphere” as it floated on the surface of the Mediterranean and then as it dived down to 300m depth. The sound in the dive portion of the video is created from the sonification of data from the KM3NeT array that was recorded during the deployment.
“Below the Surface” highlights the extraordinary environment in which the KM3NeT array is being created and operates. The data sonification illustrates the potential of this method of data representation to connect with viewers in a deeply physical way and offers new perspectives on the data collected by KM3NeT.
Virgo, hosted at the European Gravitational Observatory (EGO) is one of the most important observatories and cutting-edge physics experiments in Europe, but it is also a popular “touristic” destination, visited every year by over 10.000 people.
Virgo is first and foremost an active laboratory, where more than one hundred scientists are at work every day to do frontier physics. How can it also be a place that people enjoy visiting? How can we make sure that they do so without disrupting research activities? This requires tackling problems of a different nature, from logistical organization to the development of a visit format adapted to different audiences.
How do we handle the organization of up to 100 visitors on site, moving through experimental areas and office buildings? How can we involve researchers, giving visitors the opportunity to hear of gravitational wave science through their voices?
How can we cater to different audiences, from elementary school students to PhD students to the general public? Where is the balance between offering an informative and educational visit, and making sure that people have fun? What changes can we implement to the spaces of the observatory to make the visit experience more interesting?
Welcoming visitors into the spaces where the magic of science happens is a manifestation of transparency, involvement and trust, that could help to build stronger relationships with society at every scale, from global to local.
Cosmic rays are energetic, subatomic particles constantly reaching the Earth atmosphere from all directions. Several technological tools currently available can be used to introduce the students to research activities in the particle physics field.
The Legnaro National Laboratories (LNL) of the Italian Istituto Nazionale di Fisica Nucleare (INFN) hosts a muon telescope formed by plastic scintillators and silicon photomultipliers mostly used for outreach purposes during the International Cosmic Day (ICD).
It is well known that local atmospheric parameters affect the rate of muons reaching the Earth’s surface. In this contribution, we investigate, together with high school and bachelor students in Physics at the University of Padova, the anticorrelation between muon counts and atmospheric pressure as measured with the muon telescope in LNL using the data collected in 2022 and 2023. The results from our analysis confirm the presence of a significant anticorrelation. Further analyses with a larger datasample allow us to improve the precision of the result, as well as possibly investigate other atmospheric-related correlations, such as with temperature and humidity and the variation in time of these correlations.
In addition, we buy a new educational tool: a Cosmic Hunter detector developed by the CAEN group. We are currently testing the instrument performances and we plan to use this instrument to confirm our results and explore new possible educational activities for students.
The aim of the Archimedes experiment is the evaluation of the interactions between vacuum energy and gravity. The vacuum energy will be weighted by a very precise balance measuring the arm tilts by the mean of interferometric readout. The experiment needs a quiet place, for this reason, the final Archimedes balance is under construction directly at the Sar-Grav laboratory in Sardinia. The laboratory is located close to Lula town in the region of the Sos Enattos mine, an area so quiet that is under study to host the third generation of gravitational wave interferometer: Einstein Telescope (ET). The Archimedes balance and its prototype are presently inside the equipped rooms in a hangar on the surface. The status of the experiment will be discussed as well as its direct fallouts like extremely low noise tiltmeters and possible search for ultralight dark matter.
The scientific objective of Archimedes is to weigh the vacuum, i.e. to investigate the role of the interaction of vacuum fluctuations with the force of gravity, using a high sensitivity balance. It will measure the small weight variations induced in two high temperature superconductors that have the property of "trapping" or "expelling" vacuum energy when their temperatures are greater or lower than their critical temperatures (thermal modulation). Only the radiative heat exchange mechanism must be used to remove or add
thermal energy to the sample as it must be isolated from any external interaction that could add energy other than the vacuum one. A cryogenic prototype at liquid nitrogen temperature is being optimised for performing the thermal modulation with help of a FEM analysis. The characterisation of different high temperature superconductors is also an important study to be explored. Most recent results will be presented.
The CNO-cycle is the dominant hydrogen burning process in stars above a temperature of 17 million Kelvin. The $^{12}$C(p,$\gamma$)$^{13}$N reaction rate is dominating the rate of this cycle in the initial phase and in the outer shells of the burning zone. Furthermore, this reaction affects the abundance ratios of $^{12}$C to $^{13}$C in stars with masses slightly above solar mass. The cross section of the $^{12}$C(p,$\gamma$)$^{13}$N reaction has been re-measured, leading to an improved extrapolation to astrophysically relevant energies.
The methods and results of two measurements of this cross section will be presented: First, at $130\,$keV to $450\,$keV in inverse kinematics overground. Second, at $330\,$keV to $640\,$keV at the Felsenkeller underground laboratory.
The 3He(α,γ)7Be reaction plays a role in two distinct astrophysical scenarios, solar fusion as well as Big Bang nucleosynthesis. The nuclear reaction cross section (expressed as astrophysical S-factor) of this reaction has been studied several times for energies E > 0.3MeV and once for energies between 0.1MeV and 0.2MeV, but never directly for energies below 0.1MeV. The energies below the measured range are relevant for solar fusion, but rely on extrapolation of the existing data. A recent theory work by Zhang et al. suggests a connection between the angular distribution of the emitted γ-rays from the 3He(α,γ)7Be reaction at E = 1 MeV and the value of S(0), the extrapolated S-factor at E=0.
At the 5 MV Felsenkeller underground accelerator, implanted 3He targets and a setup of 21 HPGe detectors are being used to study the angular distribution of this reaction at six different energies between $E_\textrm{cm}=450\,$keV and $E_\textrm{cm}=1220\,$keV. This will aid the extrapolation to lower energies and improve the precision of solar 7Be and 8B neutrino fluxes calculated in solar models, to be compared with the recent BOREXINO data on these fluxes. The contribution will report on the preliminary analysis of the angular distribution measurement.
At astrophysical energies the cross sections of nuclear processes are usually very small and cosmogenic background prevents their measurement on the Earth surface. Deep underground in the Gran Sasso Laboratory, crucial reactions involved in hydrogen burning has been measured directly at astrophysical energies by the LUNA (Laboratory for Underground Nuclear Astrophysics) Collaboration with both the 50kV and the 400kV accelerators. Presently a rich experimental program is carried on at the LUNA-400 facility with a focus on hot CNO and Neon-Sodium cycles, but this years a new exciting experimental phase is going to start thanks to acquisition of the LUNA-3.5MV facility, already installed and tested at Gran Sasso. The LUNA-3.5MV accelerator is able to provide hydrogen, helium and carbon high current beams and it will allow to explore the helium and carbon burning processes, by studying the key reactions shaping the evolution of massive stars such as 22Ne(α,n)25Mg, 13C(α,n)16O and 12C+12C. In particular, in 2023, a first data acquisition campaign will be focused on 22Ne(α,n)25Mg that for massive AGB stars represents the main source of neutrons, affecting the total abundances of the elements heavier than Fe.
The present contribution is aimed to summarise the most recent results achieved by LUNA Collaboration at the 400kV accelerator, in particular on the NeNa cycle, and to highlight the next steps of the experimental program connected to the new facility.
The question whether an annual modulation is observable during nuclear decay rate measurements has long been the subject of research. One of the possible explanations for the annual variations would be the effect of solar neutrinos, the flux of which changes in correlation with the Earth-Sun distance. A decay rate measurement with a 137Cs source and a HPGe detector is currently being conducted 30 meters below the ground at Jánossy Underground Research Laboratory (Csillebérc, Hungary). The laboratory is part of the Vesztergombi High Energy Laboratory (VLAB), one of the TOP 50 research infrastructures in Hungary. Up to May 2023, data of six months' worth has been collected, and hence this is a new opportunity to check whether the annual variation in decay rate can be observed. I will present the laboratory, the experiment, and the data processing method.
Further details at
https://taup2023.hephy.at/social-events/
Brady will present the current state of ground-based, gravitational-wave astronomy and the prospects for observations over the next decade. He will present highlights from LIGO-Virgo-KAGRA (LVK) observing runs. Brady will discuss how planned detector improvements will enable unprecedented measurements of masses, spins, and other properties of black holes and neutron stars in binary systems. These improvements may also open new discovery spaces for other gravitational-wave sources. The talk will end with a discussion of future directions for upgrading the LIGO, Virgo and KAGRA detectors and how this may fit with plans for next-generation facilities such as Cosmic Explorer and Einstein Telescope.
Gravitational waves (GWs) are the newest tool for exploring the Universe. Advanced Virgo and Advanced LIGO have opened a new window on the Universe, detecting GW signals in the Hz-kHz frequency range. The Pulsar Timing Array experiments have just announced the detection of GWs in the nano-Hz frequency range.
A new generation of GW interferometric observatories is under preparation and will take over from the current generation of GW detectors in the next decade. This will make it possible to probe almost the entire Universe for GW signals. The Einstein Telescope (ET) and the Cosmic Explorer (CE) are at the forefront of the design, preparation and realisation of a next-generation gravitational wave observatory in Europe and the USA respectively. The space-based GW detector LISA will be launched in the next decade and will complete the new series of GW observatories.
With a special focus on the Einstein Telescope observatory, an overview of the scientific objectives, the observatory design, the required technologies and the project organisation will be presented.
For thousands of years we have been looking at the universe with our eyes.
Since September 14th , 2015, everything is different: Gravitational waves were discovered! Gravitational wave astronomy on the earth has become routine. Laser interferometers will soon be able to listen to low frequencies with detectors in space. Since 30 years we have been developing the LISA mission. With the mission adoption this year we will enter the Phase B2 to approach a mission launch in 2035.
The MeV band, a relatively unexplored region of the electromagnetic spectrum, holds great potential for unraveling fundamental astrophysical phenomena. It offers valuable insights into diverse areas such as the Galactic production of elements, the magnetic field configurations surrounding black holes and neutron stars, the mergers of neutron stars, and energy releases associated with hadronic accelerators. Excitingly, NASA's Compton and Spectrometer Imager (COSI) is poised to embark on a comprehensive study of the entire sky, finally shedding light on this fundamental energy range.
In this presentation, we will delve into COSI's primary science capabilities, focusing on multi-messenger and time-domain astronomy. By exploiting the unique observational strengths of COSI, we can anticipate a wealth of discoveries and breakthroughs that will significantly benefit the wider scientific community. Join us as we explore the untapped potential of the MeV band and uncover the cosmic secrets that COSI holds in store.
Diversity is crucial to boosting productivity and innovation, fighting prejudice and discrimination and improving social and economic standards. Nonetheless, high-energy physics and astrophysics remain one of the less diverse fields in science. With ever-growing international collaborations reaching thousands of members from all around the world, diversity and inclusion issues have become critical. In this presentation, I will discuss the current situation in terms of diversity and inclusion in high-energy physics and astrophysics, highlighting progress and challenges. I will also discuss actions and best practices undertaken to promote diversity and inclusion in large collaborations, organisations or research institutions.
Many well motivated dark matter (DM) particle candidates can decay into detectable X-ray photons. We analyze eROSITA Final Equatorial Depth Survey (eFEDS) from eROSITA early release data to search for unexplained X-ray lines that could indicate DM signal. Having discovered no extra line, we set limits on DM decay rate in mass range between $2-18$\,keV, and constrain the parameter space of 3 DM particles: sterile neutrino, Axionlike particles, and dark photon. Finally we also study the projected sensitivity of eROSITA full sky search, showing that eROSITA is expected to set stringent limits in the soft X-ray band.
The Short-Baseline Near Detector (SBND) is a 112-ton liquid argon time projection chamber (LArTPC) detector located 110-meters downstream the Booster Neutrino Beam target at Fermilab. As the near detector of the Short-Baseline Neutrino Program, SBND is especially sensitive to any new particles produced in the beam. In addition to the excellent spatial and energy resolution of the LArTPC technology, SBND features photon detection and cosmic–ray tagger systems achieving ns-time resolution. In this talk we will review SBND’s capabilities and prospects for searches for Beyond Standard Model physics such as heavy neutral leptons, sub-GeV dark matter, and dark neutrinos.
The exquisite capabilities of liquid Argon Time Projection Chambers make them ideal to search for weakly interacting particles in Beyond the Standard Model scenarios. Given their location at CERN the ProtoDUNE detectors may be exposed to a flux of such particles, produced in the collisions of 400 GeV protons (extracted from the Super Proton Synchrotron accelerator) on a target. Here we point out the interesting possibilities that such a setup offers to search for both long-lived unstable particles (Heavy Neutral Leptons, axion-like particles, etc) and stable particles (e.g. light dark matter, or millicharged particles). Our results show that, under conservative assumptions regarding the expected luminosity, this setup has the potential to improve over present bounds for some of the scenarios considered. This could be done within a short timescale, using facilities that are already in place at CERN, and without interfering with the experimental program in the North Area.
The nature of Dark Matter is an ongoing and relevant object of study in astroparticle physics. Despite our best efforts to identify its possible particle properties, the results have been null, which has led to a plethora of models describing viable connections to the Standard Model. In particular, loop models of Dark Matter, like the scotogenic model, have received attention in the last decade but their phenomenology in regard to Dark Matter interactions with neutrinos has not been widely studied in a global analysis. We aim to explore whether parameters of a one-loop model of scalar Dark Matter-neutrino interactions such as the DM mass, the mediators' masses, and the couplings can be constrained by performing a Bayesian and a frequentist analysis using data on the DM relic abundance, BBN and $N_\mathrm{eff}$, the lightest neutrino mass, and meson decays.
The presence of dark matter can explain several observations in the universe. However, its nature is still unknown. Therefore, the study of dark matter is a rapidly evolving field. New techniques and methods are being applied all the time. The measurement of the direction of WIMP-induced nuclear recoils is a challenging strategy to extend dark matter searches beyond the neutrino floor and provide an unambiguous signature of the detection of Galactic dark matter. The sensitivity of gas detectors are limited by the small achievable detector mass to reach the neutrino floor. NEWSdm is an innovative directional experiment proposal based on the use of a solid target which is made by newly developed nuclear emulsion and read-out systems achieving a position accuracy of 60 nm. The nuclear emulsion technology is the most promising technique with nanometric resolution to disentangle the dark matter signal from the neutrino background. In this talk, we discuss the experiment design, its physics potential, the near-future plans. After the submission of a Letter of Intent, a new facility for emulsion handling was constructed in the Gran Sasso underground laboratory and different measurements have been carried out, including the first directional measurement of sub-MeV neutrons. A Conceptual Design Report is in preparation and will be submitted in 2023.
The sensitivity of the direct dark matter search is being improved by various energy-sensitive experiments such as XENONnT, LZ, Panda-X and so on. On the other hand, in order to reveal properties of the dark matter particle after its discovery or to explore beyond the neutrino floor region, direction-sensitive dark matter search is designed and taken place recently. NEWAGE the direction-sensitive WIMP search experiment using three-dimensional tracking gaseous TPC detector placed in an underground laboratory at Kamioka Observatory. Recently the sensitivity is improved by implementing new ambient gamma-ray rejection cut and a head-tail determination analysis. Furthermore, we are commissioning the larger scale gaseous TPC in parallel with the development of low RI emission micro pattern gas detector. This presentation reports the status and the future prospects of our underground dark matter search experiment.
The CYGNUS proto-collaboration aims to establish a Galactic Directional Recoil Observatory at the ton-scale that could test the DM hypothesis beyond the Neutrino Floor and measure the coherent and elastic scattering of neutrinos from the Sun and possibly Supernovae. A unique capability of CYGNUS will be the detailed measurement of topology and direction of low-energy nuclear and electron recoils in real time. Other key features of CYGNUS are modular, recoil sensitive TPCs (electron and/or negative ion drift operation) filled with a Helium-Florine based gas mixture at atmospheric pressure for sensitivity to low WIMP masses for both Spin Independent and Spin Dependent couplings. Installation in multiple underground sites (including the Southern Hemisphere), with a staged expansion, is foreseen to mitigate contingencies, minimise location systematics and improve sensitivity. We will review the key features and expected physics reach of CYGNUS, and the programs currently underway in the collaboration laboratories to optimise gas mixture, technologies and algorithms towards the realisation of this concept.
We are going to present the CYGNO project for the development of an high precision optical readout gaseous Time Projection Chamber (TPC) for directional Dark Matter search and solar neutrino spectroscopy, to be hosted at Laboratori Nazionali del Gran Sasso (LNGS). CYGNO peculiar features are the use of sCMOS cameras and PMTs coupled to GEMs amplification of an helium-fluorine based gas mixture at atmospheric pressure. The goal is to achieve 3D tracking with head tail capability and background rejection down to O(keV) energy, to boost sensitivity to low WIMP masses for both Spin Independent and Spin Dependent coupling. We will illustrate the commissioning and the underground operation of the 50 L prototype LIME, the largest developed so far by the collaboration, and its capability to measure and identify low energy nuclear and electron recoils. We will outline the design and prospects for the development of the already funded O(1) m3 demonstrator to be hosted in Hall F of LNGS and illustrate the physics reach of a possible future O(30) m3 experiment emerging from these developments. We will furthermore discuss the R&D results obtained by the collaboration towards the maximisation of the CYGNO potentialities, and in particular the recent demonstration of negative ion drift operation at atmospheric pressure with optical readout obtained in sinergia with the ERC Consolidator Grant project INITIUM.
The invention of skipper-CCDs with sub-electron noise has paved the way for groundbreaking low-threshold dark matter (DM) experiments, such as DAMIC and SENSEI. Conventionally, these experiments are deployed underground to mitigate cosmogenic backgrounds; however some dark matter signatures are inaccessible to underground experiments due to attenuation in the Earth’s atmosphere and crust. The DarkNESS mission will deploy an array of skipper-CCDs on a 6U CubeSat in Low Earth Orbit (LEO) to search for electron recoils from strongly-interacting sub-GeV dark matter as well as X-ray signatures of DM annihilation or decay. Using a series of observations from LEO, the DarkNESS mission will set competitive lower limits on the DM-electron scattering cross section and help inform the experimental conundrum associated with the purported observation of an unidentified 3.5 keV X-ray line, potentially produced from sterile neutrino decay. This contribution will describe the DarkNESS instrument, report the scientific objectives of the DarkNESS mission and the DM parameter space that DarkNESS will probe, as well as outline the technical challenges in using skipper-CCDs in a space-based environment.
The search for electronic transitions induced by the scattering of Milky Way dark matter (DM) particles in detector materials has attracted a great deal of attention in recent years as it can probe DM masses that are not accessible in conventional nuclear recoil experiments. In this talk, I introduce a formalism that can describe the scattering of DM particles by electrons bound in detector materials for a general form of the underlying DM-electron interaction. The formalism predicts a factorisation of the DM and material physics input to the DM-induced electronic transition rate, and combines a non-relativistic effective theory for DM-electron interactions with material response functions defined in terms of electron wave function overlap integrals. To illustrate the generality of this approach, I apply our formalism to interpret the null result reported by operating DM direct detection experiments, and to assess the potential of graphene and nanotubes as next-generation directional DM detectors.
We propose a method for detecting single chiral phonons and their use as directional dark-matter detectors with O(meV) energy thresholds. This detection mechanism would be capable of exploring a multitude of unprobed dark-matter candidates as well as serve as a quantum sensor that can open up new directions in precision measurements for experimental physics.
Nuclei that are unstable with respect to double beta decay are investigated in this work for a novel Dark Matter (DM) direct detection approach. In particular, the diagram responsible for the neutrinoless double beta decay can be considered for the possible detection technique of a Majorana DM fermion in-elastically scattering on a (double beta) unstable nucleus, stimulating its decay. The exothermic nature of the stimulated double beta decay would allow the direct detection of light DM fermions, a class of DM candidates that are difficult or impossible to investigate with the traditional elastic scattering techniques. The phenomenology of this DM detection approach and the expected signal distribution for different DM masses will be shown for a simple interaction model. The comparison with the existing experimental data for the case of 136Xe nucleus and the upper limits on the nucleus scattering cross sections will be presented, considering the example of the (116.7 kg x yr) exposure collected by the EXO-200 experiment. The proposed approach could be very effective for the investigation of MeV/sub-GeV fermionic DM using the existing or planned neutrinoless double beta decay experiments.
In this talk, we present and discuss the latest results of the SENSEI experiment at SNOLAB. We will also discuss the prospects for rare event searches with skipper-CCDs. Skipper-CCDs are pixelated silicon-based detectors that can perform multiple non-disruptive measurements of the same charge package. Their sub-electron resolution allows the detection of eV energy transfers, such as that expected from light-dark matter interacting with electrons in a silicon target. SENSEI (Sub-Electron Noise Skipper Experimental Instrument) was the first experiment to implement skipper-CCD for this purpose and to produce world-leading results using this technology.
The DAMIC-M experiment employs thick, fully depleted silicon charge-coupled devices (CCDs) to search for sub-GeV dark matter particles. Thanks to its multiple non-destructive measurements of the pixel charge, DAMIC-M skipper CCDs achieve single-ionization charge resolution and an energy threshold in the eV-scale. We report on the progress of the experiment and first results from prototype detectors installed underground at the Laboratoire Souterrain de Modane. In particular, constraints on dark matter particles interacting with electrons are obtained in a mass range between 0.5 and 1000 MeV. We also present results of a search for diurnal modulation in the measured single-ionization charge rate which significantly improves sensitivity at the lowest masses.
We present results from a 3.1 kg-day target exposure of two 24-megapixel skipper charge-coupled devices (CCDs) deployed in the DAMIC setup at SNOLAB. With a $10\times$ reduction in pixel noise, we investigate the excess population of low-energy bulk events previously observed. We address the dominant systematic uncertainty of the previous analysis through an improved strategy to reject CCD surface backgrounds by depth fiducialization. The observed energy spectrum and spatial distribution of ionization events with electron-equivalent energies $<$500 eV confirm the presence of a bulk excess compatible with previous findings. This measurement establishes the existence of a prominent source of low-energy events in the CCD target with characteristic rate of ${\sim}10$ events per kg-day, and energies ${\sim}100~$eV, whose origin remains unknown.
Due to its unique geophysical features and to the low population density of the area, Sos Enattos is a promising candidate site to host the Einstein Telescope (ET), the third-generation Gravitational Wave Observatory. The characterization of the Sos Enattos former mine, close to one of the proposed ET corners, started in 2010 with the deployment of seismic and environmental sensors underground. Since 2019 a new extensive array of seismometers, magnetometers and acoustic sensors have been installed in three stations along the underground tunnels, with one additional station at the surface. Two boreholes 270 m deep were excavated at the other two corners, determining the good quality of the drilled granite and orthogneiss rocks and the absence of significant thoroughgoing fault zones. These boreholes are instrumented with broadband seismometers that revealed an outstanding low level of vibrational noise in the low-frequency band of ET-LF (2-10Hz), beating the Peterson's NLNM and resulting among the quietest seismic stations in the world in that frequency band. The low seismic background and the reduced number of seismic glitches ensure that just a moderated Newtonian noise subtraction would be needed to achieve the ET target sensitivity. Active seismic campaigns have been carried out to reveal the features of the subsoil. Finally, temporary arrays of seismometers, magnetometers and acoustic sensors are deployed in the area to study the local sources of environmental noise.
We designed MoonLIGHT (Moon Laser Instrumentation for General relativity/geophysics High accuracy Tests), a single 100 mm-large next-generation lunar retroreflector for lunar laser ranging operations, able to support a millimeter range accuracy and below. MoonLIGHT and its automated, dual MoonLIGHT Pointing Actuator (MPAc) has been selected by ESA for launch in NASA’s programs Commercial Lunar Payload Services and Payload and Research Investigations on the Surface of the Moon-1A (CP-11). MPAc will be flown to the Moon on-board the Nova-C lander of Intuitive Machines n.3 mission in April 2024. With its capabilities, MoonLIGHT will contribute to probe gravity through higher precision tests of general relativity and beyond, to improve lunar surface selenodesy, and to enhance our knowledge of the geophysical properties of the interior of the Moon. The imminent ESA and NASA lunar surface missions, like CP-11 in 2024, will establish a solid heritage for future opportunities employing retroreflectors like MoonLIGHT. In the next decade, the proposed lunar gravitational-wave detectors may benefit of this heritage to perform laser-interferometry based on retroreflectors like MoonLIGHT and its MPAc pointing actuators. Applications are proposed for international projects like Lunar Seismic and Gravitational Antenna (LSGA) and/or Laser Interferometer Lunar Antenna (LILA). For a reflector deployment with a rover, a robotic dust cover (under development by INFN) will also be beneficial.
We illustrate a comprehensive study of the 2HDM+a coupled with Dark Matter, including constraints from collider and dedicated Dark Matter searches. We also illustrate the outcome analysis of the cosmic phase transitions and the gravitational wave spectrum that are implied by the model and show the prospects for observing the signal of such gravitational waves in near future experiments such as LISA, BBO or DECIGO.
The presence of dark matter overdensities surrounding a black hole can influence the evolution of a binary system. The gravitational wave signals emitted by a black hole binary offer a promising means to probe the dark matter environments near a black hole. The dense region of dark matter can lead to the dephasing of gravitational waveforms, which can be detected by upcoming experiments such as the Laser Interferometer Space Antenna (LISA). The dark matter density profile around the black hole can vary for different dark matter models. Our study specifically investigates the impact of the ultralight self-interacting scalar dark matter (SIDM) on the gravitational wave signals emitted by black hole binaries. A distinctive characteristic of SIDM surrounding a black hole, as opposed to collisionless dark matter, is the formation of a soliton core. We perform a Fisher matrix analysis to estimate the size of the soliton and the corresponding SIDM parameter space that future LISA-like gravitational wave experiments can explore.
Restoration of left-right symmetry at high energy scales provides a well-motivated extension of the Standard Model, which has been scrutinized over the past few decades, chiefly in context of collider experiments. In my talk I will present a complementary approach and investigate whether these models can be probed via the search for a stochastic gravitational wave background induced by the left-right phase transition. A prerequisite for this kind of gravitational wave production is a first-order phase transition, occurrence of which can be found in a significant portion of the parameter space. Although the produced gravitational waves are typically too weak for a discovery at any existing or planned detector, upon examining correlations between all relevant terms in the scalar potential, parameters leading to observable signals can be identified. This indicates that the minimal left-right symmetric model features another powerful probe which can lead to either novel constraints or remarkable discoveries in the near future.
The combined interpretation of the spectrum and composition measurements plays a key role in the quest for the origin of ultra-high-energy cosmic rays (UHECRs). The Pierre Auger Observatory, thanks to its huge exposure, provides the most precise measurement of the energy spectrum of UHECRs and the most reliable information on their composition, exploiting the distributions of the depth of maximum of the showers in the atmosphere.
A combined fit of a simple astrophysical model of UHECR sources to the spectrum and mass composition measurements is used to evaluate the constraining power of the data measured by the Pierre Auger Observatory on the source properties. We find that our data across the “ankle” feature are well reproduced if two extragalactic populations of sources are considered, one emitting a very soft spectrum which dominates the region below the ankle, and the other taking over at energies above the ankle, with an intermediate mixed composition, a hard spectrum and a low rigidity cutoff. Interestingly, similar results can also be obtained if the medium-mass contribution at lower energy is provided by an additional Galactic component.
The Pierre Auger Observatory upgrade, AugerPrime, will significantly improve the measurement of the mass composition beyond the present limit, which will allow us to perform a similar combined analysis with much larger statistics at the highest energies.
Gamma rays, high-energy neutrinos and cosmic rays (CRs) impinging on Earth signal the existence of environments in the Universe that allow acceleration of particle populations into the extremely energetic regime. In order to understand these observable signatures from putative CR sources in-source acceleration of particles, their energy and time-dependent transport including interactions in an evolving environment and their escape from source have to be considered, in addition to source-to-Earth propagation.
Low-luminosity jets of Active Galactic Nuclei (AGN) constitute the most abundant persistent jet source population in the local Universe. The dominant subset of these, Fanaroff-Riley 0 (FR0) galaxies, have recently been proposed as sources contributing to the ultra-high-energy cosmic ray (UHECR) flux observed on Earth. This presentation assesses the survival, workings and multi-messenger signatures of UHECRs in low-luminosity jet environments, with focus on FR0 galaxies. For this purpose we use our recently developed, fully time-dependent CR particle and photon propagation framework which takes into account all relevant secondary particle production and energy loss processes, allows for an evolving source environment and efficient treatment of transport non-linearities due to the produced particles/photons being fed back into the simulation chain.
The low luminosity Fanaroff-Riley type 0 (FR0) radio galaxies are amongst potential contributors to the observed flux of ultra-high energy cosmic rays (UHECRs). Due to their much higher abundance in the local universe with respect to more powerful radio galaxies (e.g., FR0s are about five times more ubiquitous at redshifts z≤0.05 than FR1s), FR0s could provide a substantial fraction of the total UHECR energy density.
In the presented work we determine the mass composition and the energy spectrum of UHECRs emitted by FR0 sources by fitting simulation results from CRPropa3 framework to the recently published Pierre Auger Observatory data. The resulting emission spectral characteristics (spectral indices, rigidity cutoffs) and elemental group fractions are compared to the Auger results. The FR0 simulations include the approximately isotropic distribution of FR0s extrapolated from the measured FR0 galaxy properties, and various extragalactic magnetic field configurations including random and large-scale structured fields. We predict the fluxes of secondary photons and neutrinos produced during UHECR propagation through cosmic photon backgrounds. The presented results allow for probing the properties of the FR0 radio galaxies as cosmic-ray sources using observational high-energy multi-messenger data.
Blazars are characterized by relativistic jets oriented at a small angle to the observer's line of sight. They are among the most powerful and long-lived astrophysical sources in the Universe, with spectral energy distributions spanning 20 orders of magnitude of frequencies. The recent observation of a neutrino, coincident with a flaring blazar, TXS 0506+056, has opened a new era in blazar research – that of multi-messenger observations when a blazar can be studied by detecting photons and neutrinos. I will review the recent possible association between neutrinos and blazars and present multimessenger blazar spectral energy distribution modelling using the SOPRANO code. SOPRANO is a new, conservative, implicit kinetic code that traces the time evolution of isotropic distribution functions of protons, neutrons, and secondary products from photo-pion and photo-pair interactions, alongside the evolution of photon and electron/positron distribution functions. I will also focus on the blazar PKS 0735+178, which is potentially associated with multiple neutrino events as observed by the IceCube, Baikal, Baksan, and KM3NeT neutrino telescopes. I will present a detailed study of this peculiar blazar, investigating the temporal and spectral changes in multi-wavelength emission when the neutrino events were observed as well as will also present results from comprehensive modelling of the multi-wavelength emission from PKS 0735+178 within lepto-hadronic models.
Star forming region(SFR) has long been suggested as the factory of galactic cosmic rays. It has attracted more interest with the progress from observation. An ultra-high energy photo with energy of 1.4PeV was detected from Cygnus region, which implies there might be a super accelerator in this region. The detection of UHE gamma ray emission (above 100TeV) is crucial to understand the properties of particle acceleration and propagation around clusters. LHAASO is a dual-purpose complex of particle detectors, which has the highest sensitivity at UHE energy range. In this talk, we will give a brief introduction about the observation of SFRs ( Cygnus Cocoon, W43 et al) with LHAASO.
Cosmic rays are thought to be accelerated up to a few PeV by the most powerful sources, the so-called “PeVatron” in the Galaxy. On the other hand, gamma rays beyond 100 TeV are expected by the neutral pion decays caused by the interaction of these cosmic rays with the interstellar medium. Therefore, the gamma-ray observation is key to unveiling a long-standing mystery, the origin and the propagation of very-high-energy cosmic rays in the Galaxy, because gamma rays go straight unaffected by the magnetic field, pointing back to the sources.The Tibet air shower (AS) array and the underground water-Cherenkov-type muon detector (MD) array have been successfully operating, at an altitude of 4,300 m in Tibet, China since 2014. The gamma-ray energy and arrival direction are determined by the surface AS array, while the underground MD array enables us to drastically suppress the background cosmic rays above 100 TeV, by means of counting the number of muons in an air shower. Using these Tibet AS+MD arrays, we have succeeded for the first time in observing gamma rays above 100 TeV from the Crab Nebula [Amenomori et al. PRL, 123, 051101 (2019)] and the Galactic plane [Amenomori et al. PRL, 126, 141101 (2021)]. In this presentation, we will review recent observations with the Tibet ASgamma experiment and discuss the most powerful cosmic-ray source “PeVatron” in our Galaxy.
KM3NeT is a multi-purpose neutrino observatory being installed in a phased scheme in the Mediterranean Sea. It is composed of two Cherenkov detectors instrumenting water with photomultipliers in different layouts: ORCA, a compact and dense detector optimised on the measurement of fundamental atmospheric neutrino physics, such as mass ordering and oscillations, in the 1-100 GeV energy range, with unprecedented statistics; and ARCA, a
set of two detectors covering a cubic kilometre to catch faint astrophysical neutrino fluxes from 100 GeV to 10 PeV, with a pointing resolution reaching down to 0.1 degree. Each detector has a final configuration of 115 lines, and currently 15 lines of ORCA and 21
of ARCA are recording data. An overview of first KM3NeT results and prospects will be presented, with focus on the measurement of oscillation parameters, on the search for sources of extraterrestrial neutrinos, and on the prompt multi-messenger program including the search for correlations of neutrinos with gravitational waves. The physics case of KM3NeT is broad and also covers new physics searches that will also be presented, such as non-standard oscillations, invisible neutrino decay and dark matter.
The KM3NeT/ORCA is a next-generation water Cherenkov neutrino telescope currently under construction in the Mediterranean Sea. By studying the oscillations of the atmospheric neutrino flux passing through the Earth, thanks to the detector geometry and its unprecedented statistics, KM3NeT/ORCA's primary physics goal is an early measurement of the neutrino mass ordering as well as the direct observation of tau neutrino appearance; the last, allowing for a test of the standard three-neutrino flavors paradigm.
Due to the detector's modular structure, neutrino oscillation analyses are already possible with a partially instrumented volume (currently, 6 Detection Units - KM3NeT/ORCA6 - equivalent to 5% of the final geometry). Given that the neutrino flux composition is dominated by muon neutrinos producing a track-like topology in the detector, the tau neutrino appearance can be measured on a statistical basis and observed as an excess into the shower-like topology. In this talk, a particular focus will be dedicated to the current analysis updates on the event reconstruction and selection between the two topologies; in addition, preliminary results on tau neutrino appearance in the KM3NeT/ORCA 6 geometry will be discussed.
Neutrino Non-Standard Interactions (NSIs) are proposed as extensions of the Standard Model (SM) to accommodate mechanisms for the origin of neutrino masses. The NSIs are incorporated through effective four-fermion interactions which lead to both charged-current (CC) and neutral-current (NC) interactions. The NC NSIs affect the coherent forward scattering of neutrinos on fermions in matter, ultimately leading to modifications of the oscillation probabilities of neutrinos experiencing matter potentials. Therefore, strong matter effects influencing the core-crossing trajectories of atmospheric neutrinos traversing the Earth would enhance such modifications, making neutrino telescopes ideal candidates for NSIs studies.
This work presents the results of the NSIs search with the KM3NeT/ORCA6 and ANTARES neutrino telescopes. The ORCA detector is currently under construction in the Mediterranean Sea, and its NSIs results benefit from an increased exposure (510 days), improved reconstruction and calibration methods compared to previous works and higher selection efficiencies driven by Machine Learning techniques. On the other hand, ANTARES was the predecessor neutrino telescope of ORCA and operated uninterruptedly for 14 years with 12 detection units. This work will also present the results of the NSIs search with ANTARES data collected from 2007 to 2016, providing a constraint on the NSIs parameter $\varepsilon_{\mu\tau}$ which is among the most stringent to date.
Baikal-GVD is recently the largest neutrino telescope operating in Northern Hemisphere. The detector consists of independent operational subarrays called clusters. The data collection is allowed by the design of the experiment while being in a construction phase. This contribution reviews the design and the basic characteristics of the Baikal-GVD. Some preliminary results on diffuse neutrino flux measurements with the partially completed detector will be presented.
The discovery of a bright background of astrophysical neutrinos of unknown origin by IceCube has provided a first, tantalizing glimpse of the extreme universe outside of the electromagnetic spectrum. Ten years after its discovery, however, the production mechanism and these neutrinos remain almost entirely unknown, necessitating a new generation of instruments. This talk will describe the current status and prospects of the planned Pacific Ocean Neutrino Experiment (P-ONE), which will provide a complementary approach to that taken by IceCube and IceCube-Gen2, focusing on precision measurements and the southern celestial hemisphere. Construction of P-ONE is planned to begin in 2024, leveraging an existing deep-sea research facility off the coast of British Columbia provided by Ocean Networks Canada. When completed, the instrument will provide factor-of-4-to-5 improvements in resolution compared to IceCube, expected to increase the number of known neutrino sources by an order of magnitude, and provide the best performance in complementary areas of the sky to other neutrino telescopes such as IceCube and KM3NeT.
Core-collapse supernovae (CCSNe) are known to be among the most energetic processes in our Universe and are vital for the understanding of the formation and chemical composition of the Universe. The precise measurement of the neutrino light curve from CCSNe is crucial to study the hydrodynamics and fundamental processes that drive CCSNe. The IceCube Neutrino Observatory has model-independent sensitivity within the Milky Way and some model-dependent sensitivity in the Large and Small Magellanic clouds. As IceCube detects a CCSN as a collective noise rate increase, a high signal-to-noise ratio would improve IceCube’s sensitivity. The envisaged large-scale extension of the IceCube detector, IceCube-Gen2, opens the possibility for new sensor design and trigger concepts that could increase the CCSN event rate measured with IceCube. In this talk, we present the prospects for improved detection of MeV neutrinos in IceCube-Gen2. Segmented sensors using coincidence triggers to reduce the detector noise would enable to further expand the detection horizon to model-independently cover the Large and Small Magellanic clouds. Photon collectors using wavelength-shifting technology open the possibility to build sensors with increased photo collection area while not increasing the sensor's dark noise. This allows for fast time-varying features of the light curve of nearby supernovae to be measured with greater precision and would therefore give valuable insights into the dynamics of CCSNe.
Since 2020, Super-Kamiokande (SK) detector has been updated by loading gadolinium (Gd) as a new experimental phase, “SK-Gd”. In the SK-Gd experiment, we can search low-energy electron antineutrinos via inverse-beta decay with efficient neutron identification thanks to high cross-section and high-energy gamma-ray emission of thermal neutron capture on Gd. Until July 2022, the observation is operated with the 0.01% Gd mass concentration. The neutron capture fraction on Gd is about 50%. We report the first search result for the flux of astrophysical electron antineutrinos for the energy range of O(10) MeV in SK-Gd with a 22.5×552 kton·day exposure at 0.01% Gd mass concentration of the initial stage of SK-Gd.
The Super-Kamiokande (SK) is one of the largest water Cherenkov detectors and has a sensitivity for $\mathcal{O}(1~\mathrm{MeV})$-$\mathcal{O}(100~\mathrm{GeV})$ neutrinos. For the observation of anti-electron-neutrinos of diffuse supernova neutrino background (DSNB), we have upgraded the SK with Gd to improve the distinction performance between electron- or anti-electron-neutrinos. The latter are associated with a neutron. The typical energy of DSNB is $\mathcal{O}(10~\mathrm{MeV})$. Recently, we opened the first data of the SK-Gd-phase and set an upper limit of the anti-electron-neutrino flux, which is now under preparation for publication.
In this presentation, I show the status and prospects of future analysis to lower the lower energy threshold in the $\bar{\nu}_e$ or DSNB search. It potentially brings us reactor neutrinos and further understanding of background events such as spallation and atmospheric neutrinos events. The conventional analysis has an energy threshold of 8 MeV relating to the ordinary trigger system. However, the higher energy yield of delayed neutron-captured signals of Gd opened the possibility to decrease the energy threshold by introducing a new trigger system whose energy threshold is a few MeV. This presentation includes details of the trigger system and analysis strategy, the feasibility study using an AmBe gamma and neutron source, and the prospects.
The Super-Kamiokande (SK) experiment is a neutrino observatory located in Japan. After the loading of gadolinium sulfate octahydrate to water in its detector, the SK experiment entered a new phase, known as SK-Gd.This new phase is characterized by the significant improvement in the experiment's sensitivity to low-energy electron anti-neutrinos, thus providing more reliable data for the study of neutrino sources and interactions. SK-Gd has the potential of detecting yet-unobserved neutrinos from pre-supernova (preSN) stars, which are massive stars at the last evolutionary stage before core-collapse supernova (CCSN). The main cooling mechanism of preSN stars is the neutrino emission through different thermal and nuclear processes such as pair annihilation and beta decay, emitting high fluxes of electron anti-neutrinos. The detection of preSN neutrinos would not only help determine the neutrino mass hierarchy, but it could also provide early warnings for nearby CCSNs. In October 2021, SK launched its pre-supernova alarm. We report the sensitivity of the Super-Kamiokande detector to preSN neutrinos and information regarding the alert system. A combined alarm with the Kamioka Liquid-scintillator Antineutrino Detector (KamLAND) is currently in development to improve the sensitivity of preSN neutrinos and extend early warnings to CCSN. Details of the joint alarm are also presented as well as the expected improvement in the sensitivity for combining the results from both experiments.
When a massive star dies and, its core collapses, most of its gravitational binding energy is released as neutrinos. These neutrinos are messengers that can provide information on the supernova’s dynamics and properties of neutrinos. However, core-collapses are rare in our galaxy. The Diffuse Supernova Neutrino Background (DSNB) provides an alternative opportunity to detect these supernova neutrinos. The DSNB is the constant flux of neutrinos and antineutrinos emitted by all past CCSNe in the observable Universe.
In this talk, I will present the potential to extract information on the neutrino lifetime from the observation of the DSNB flux [1]. The DSNB flux has a unique sensitivity to neutrino non-radiative decay for $\tau/m\in[10^9,10^{11}]$ s/eV. Firstly, I will introduce the description of the DSNB flux used in our work and the effect neutrino decay has on it. Our description integrates, together for the first time, astrophysical uncertainties, the contribution from failed supernovae and a three-neutrino description of neutrino non-radiative decay. Furthermore, I will show our predictions for future detection at the running Super-Kamiokande + Gd, and the upcoming Hyper-Kamiokande, JUNO, and DUNE experiments. Finally, I will stress the importance of identifying the neutrino mass ordering to restrict the possible decay scenarios for the impact of non-radiative neutrino decay on the DSNB.
[1] P. Iváñez-Ballesteros and M. C. Volpe, Phys. Rev. D, 107 023017, arXiv:2209.12465
The Deep Underground Neutrino Experiment (DUNE) is a next-generation long-baseline experiment exploiting the liquid argon TPC technology. DUNE will have sensitivity to low energy physics searches, such as the detection of supernova and solar neutrinos. DUNE will consist of four modules of 70-kton liquid argon mass in total, placed 1.5 km underground at the Sanford Underground Research Facility in the USA. These modules are being designed considering the specific requirements of the low energy physics searches. As a result, DUNE will have a unique sensitivity for the detection of electron neutrinos from a core-collapse supernova burst, and solar and diffuse supernova background neutrinos can also be detected.
SNO+ is a large, optical neutrino detector with a broad research program. The primary goal of SNO+ is to search for neutrinoless double beta decay using tellurium-loaded liquid scintillator. The experiment first took data while the detector was filled with the water but is now completely filled and collecting data with liquid scintillator. In this talk I will discuss the physics results from the SNO+ water phase, highlighting measurements of the $^{8}$B solar neutrinos with extremely low backgrounds and the first measurement of reactor neutrinos in a water Cherenkov detector. I will then detail the status and plans for the neutrino measurements during the liquid scintillator phase, focusing on solar and reactor neutrino sensitivities.
The Extreme Energy Events (EEE) project was born to include scientific, outreach and educational purposes.
It is designed to detect and study high energy cosmic rays through the detection of the shower’s muon component through several muon telescopes based on Multigap Resistive Plate Chambers (MRPC) synchronized by GPS. The telescopes are organized in local clusters and single telescope stations distributed all over the Italian territory and installed in high schools buildings.
These unconventional working sites offer young students the opportunity to get in touch with the world of high energy physics research. Every year hundreds of students and teachers are involved in the activities directly correlated to EEE.
The EEE Collaboration planned an intense plan of on-line activities: monthly collaboration meetings, masterclasses and seminars. With enormous success and participation, even activities focusing on the upgrade phase of the EEE project have been recently carried out in the last two years. The idea is to continue and to increase the activities in presence to stimulate the students and to provide opportunities for engaging students in learning physics and carrying data analysis sessions.
This contribution will present a general overview of the EEE outreach activities and the future plan.
The IPPOG collaboration celebrated its 25th anniversary in 2022: initiated at CERN in the early days of LHC, it now counts 33 countries around the globe, 6 scientific collaborations and 3 international laboratories. Looking back at the activities, there is an increased connection between collider and astro-particle physics outreach communities. This synergy is expected to benefit both communities, and already plays a key role in the discussions on future HEP projects.
As an illustration of that process, the EUTOPIA project at LAPP, Annecy, will be presented. Building on prior efforts by the French national institute (IN2P3) coordinating research on “the two infinites”, particle physics and cosmology, a visitor centre opened in 2019. It presents open questions and technical challenges to stakeholders, students, teachers and the general public. The benefit of combining “open days” with “outside the walls” events and visits to class-rooms will be discussed.
Masterclasses are one-day outreach events for high school students, introducing them to topics of current research. Within the framework of the EU project ChETEC-INFRA, Masterclasses on Nuclear Astrophysics have been developed. This interdisciplinary field of science provides a new didactic perspective on nuclear and astrophysical processes by addressing the link between these two subjects. The Nuclear Astrophysics Masterclasses pick up this didactic potential. They include the analysis of measurement data from nuclear reactions studied at the Felsenkeller underground ion accelerator Laboratory in Dresden, Germany. Furthermore, the processes behind the formation of the chemical elements - from primordial nucleosynthesis to s- and r-processes - are reconstructed with the help of various gamification elements as well as hands-on activities like astronomical spectroscopy. The talk will present the teaching materials, the didactic concept and the experiences made so far in the implementation of the Masterclasses.
International Masterclasses - hands-on particle physics (IMC) is an annual programme for high school students organized by the International Particle Physics Outreach Group (IPPOG) in collaboration with universities and research centres around the globe. In a single day, the students are fully immersed in the activities and challenges of modern research. From morning lectures to afternoon hands-on measurements with real data from large experiments, they have the opportunity to listen to scientists, ask questions and seek professional guidance in solving problems during the data analysis. At the end of the day, the students from several countries join the video conference to discuss their results at the international level. The IMC physics topics include all major LHC experiments, Belle II, Particle Therapy Masterclass, Minerva and, the latest addition, Pierre Auger Masterclass. IMC continue their geographical expansion and currently attract more than 13 000 students from 60 countries every year. We describe the main features of the programme including its growing physics scope.
DARK is an INFN outreach activity related to gravitation, dark matter and dark energy. Three main activities were performed during the recent years. For high school students we performed since 2020 the Dark Matter Masterclasses, including theory and experimental introduction to dark matter, an exercise based on the DarkSide-50 experiment simulation and theory and an exercise related to the cryogenic distillation, related the Aria project. These MasterClasses are repeated on a yearly basis in various towns in Italy. Also, during the COVID times we performed the online meetings entitled “Nuovi discorsi sui Massimi sistemi” (the title is related to a famous Galileo’s book) related to the confrontation of physics with philosophy in the field of gravity and dark matter and energy. For the general public we also organised last year the first edition of “GravitasFest” in person, which will be repeated on a yearly basis in various town in Italy, a festival where gravity is confronted with philosophy, sociology, art and theatre.
Restricted meeting, by invitation only.
The QUEST-DMC experiment aims to utilise superfluid He-3 instrumented with quantum sensors to access sub-GeV dark matter parameter space. The experiment will have a superfluid 3-He target, operated below 100 microKelvin, contained in cubic cells instrumented with nanomechanical resonators read out by SQUIDs.
Superfluid He-3 is an ideal target medium for sub-GeV dark matter searches, in particular spin-dependent interactions, as well as a wide range of theoretically well-motivated models. The small superfluid energy gap for quasiparticle excitations, 1E-7 eV, and amplification of signals from Andreev scattering make the system a unique bolometer. With the addition of very low noise readout using quantum sensors there is the potential to reach ultra-low energy thresholds, below the eV scale.
Here, we will present work on optimisation and projected sensitivity of the experiment, plus development of the key enabling technologies. This includes background assay results and GEANT4 simulations, modelling of the detector response and readout noise. The resulting projected sensitivity of the experiment to various dark matter models will be presented. Recent developments in nanowire fabrication, bolometric measurements and quantum sensor readout will also be shown.
The search for dark matter has recently broadened to focus on a much wider class of candidates, including particle-like dark matter lighter than the traditional WIMP. The SPICE/HeRALD (or TESSERACT) collaboration has been formed to search for light (MeV-GeV) dark matter interactions in a variety of targets read out by TES-based calorimeters. In this talk, we describe the efforts of the SPICE project to search for light dark matter using crystalline targets including the polar crystals GaAs and Sapphire. We will detail specific thrusts of our ongoing R&D efforts: reducing low-energy backgrounds, improving energy resolution, and conducting pathfinder sub-GeV dark matter searches.
We report recent progress toward using superfluid 4He for nuclear recoil direct detection, as part of the overall TESSERACT pre-Project R&D effort. in the US. The 4He "quantum evaporation" signal pathway allows both a low threshold and the possibility of rejecting the primary background (heat-only events in the calorimetry itself) through multi-channel coincidence. We have recently demonstrated the key technology of heat-free superfluid film-stopping, newly allowing measurements of 4He scintillation and evaporation signal yields at sub-keV energies.
Developments over the last decade have pushed the search for particle dark matter (DM) to new frontiers, including the keV-scale lower mass limit for thermally-produced DM. Galactic DM at this mass is kinematically matched with the energy needed to break a Cooper pair in common superconductors (~meV). Quantum sensors such as superconducting qubits are sensitive to these broken Cooper pairs, and can potentially be exploited as low-threshold detectors for particle-like DM scattering. The Quantum Science Center group at Fermilab is using two test facilities to pursue development of such sensors for DM detection. A surface facility, LOUD, has been commissioned and is being operated to explore the capabilities of a variety of quantum sensors as elements of novel low-mass DM detection schemes. A dedicated underground partner facility, QUIET, is currently being commissioned and will be used for operation of select devices in a low-background environment. This talk will discuss recent progress on these facilities and devices tested, and the plans to leverage them for DM detection down to the keV-scale.
BULLKID is an innovative cryogenic particle detector to search for low-energy nuclear recoils at the 100 eV energy scale.
It consist of an array of 60 silicon absorbers of 0.3 g each sensed by phonon-mediated, microwave-multiplexed Kinetic Inductance Detectors.
The total active mass is 20 g but the tecnology is designed to be easily scalable to 1 kg.
BULLKID's unique feature consists in being a fully active and monolithic array.
This enables volume fiducialization and allows background rejection down to the lowest detectable energies, a key requirement for experiments on low-mass Dark Matter.
In this talk I will present our new and promising results, and the prospects for a future experiment.
While the search for Dark Matter in the form of massive WIMPs sets stronger and stronger limits, the low mass region of the DM-nucleon scattering parameter space has been barely probed. An efficient detection of Light Dark Matter (LDM) requires a sub-keV detection energy threshold and large exposure. Solid state detectors can reach O(10 eV) threshold, but they are limited in exposure by their relatively small size.
The “Direct search Experiment for Light dark matter” (DELight) aims at using superfluid helium-4 as target. Helium is particularly suited thanks to its low nuclear mass and radiopurity, while allowing for a scalable technology and providing both photon and quasiparticle signal channels for interaction type discrimination. DELight will deploy Magnetic Micro-Calorimeters (MMCs) operating at a temperature of 20 mK, promising high resolution and a threshold of a few eV. With an exposure of only 1 kg×d and an energy threshold of 20 eV, in its first phase DELight has sensitivity to so far unexplored regions of the parameter space for LDM masses below 100 MeV/c2 with an expected sensitivity lower than 10−39 cm2 at 200 MeV/c2.
We will present the working principle of the detector technologies as well as an overview of the ongoing R&D towards the realization of DELight.
Many low-threshold experiments observe sharply rising event rates of yet unknown origins below a few hundred eV, and larger than expected from known backgrounds. Due to the significant impact of this excess on the dark matter or neutrino sensitivity of these experiments, a collective effort has been started to share the knowledge about the individual observations. For this, the EXCESS workshop was initiated. Its fourth iteration is part of the TAUP 2023 conference as a satellite workshop, and we will report a summary of the event, conclusions, and further plans in this contribution.
COSINE-100 is a dark matter direct detection experiment aimed at verifying DAMA/LIBRA's claim of observing annual modulation signals using NaI(Tl) crystals. Between September 2016 and March 2023, the COSINE-100 experiment collected physics data at the Yangyang underground laboratory in Korea using 106 kg of NaI(Tl) crystals. The detector assembly design is currently being upgraded to increase light collection efficiency in preparation for new operation at the Yemilab, a new underground laboratory in Korea, which is planned to start from October 2023. Moreover, COSINE collaboration is developing a high-purity NaI(Tl) detector for the next phase COSINE-200 experiment. This presentation will provide an update on the current status and future prospects of both COSINE-100 and COSINE-200 experiments.
The ANAIS (Annual modulation with NaI(Tl) Scintillators) experiment is intended to search for dark matter annual modulation with ultrapure NaI(Tl) scintillators in order to provide a model independent confirmation or refutation of the long-standing DAMA/LIBRA positive annual modulation signal in the low energy detection rate, using the same target and technique. Other experiments exclude the region of parameters singled out by DAMA/LIBRA. However, these experiments use different target materials, so the comparison of their results depends on the models assumed for the dark matter particle and its distribution in the galactic halo. ANAIS−112, consisting of nine 12.5 kg NaI(Tl) modules produced by Alpha Spectra Inc., disposed in a 3×3 matrix configuration, is taking data smoothly with excellent performance at the Canfranc Underground Laboratory, Spain, since August, 2017. Last published results corresponding to three-year exposure were compatible with the absence of modulation and incompatible with DAMA/LIBRA for a sensitivity of 2.5-2.7σ C.L. Present status of the experiment and a reanalysis of the first 3 years data using new filtering protocols based on machine-learning techniques will be reported in this talk. This reanalysis allows to improve the sensitivity previously achieved for the DAMA/LIBRA signal. Updated sensitivity prospects will also be presented: with the improved filtering, testing the DAMA/LIBRA signal at 5σ will be within reach in 2025.
The CDEX program pursues the direct detection of light dark matter candidates with an array of germanium detectors since 2009 at the deepest operating underground site, China Jinping underground laboratory (CJPL) located in Sichuan, China, with a rock overburden of about 2400m. Searches of modulation effect of light WIMPs, WIMPs-nucleus interaction via Midgal effect, dark photon model, solar axions and axion-like particles have been recently carried out based on the CDEX-1 and CDEX-10 experiments. An upgraded dark matter experiment of the CDEX-50 is proposed and on-going together with the R&D programs on many key low radioactivity technologies. Results and the prospects of the CDEX dark matter program will be described and discussed.
In recent years, the threshold of Dark Matter search experiments has been lowered, enabling the search for Dark Matter-electron scattering. In the region of interest for mass and cross-section that current experiments can reach, the propagation of particles from the Dark Matter wind through the Earth can produce a (sideral) daily modulation in the observed signal. We explore the modulation signal expected in different materials and show how a significant improvement in the current sensitivity can be obtained in the lower mass region by searching for that daily modulation. Depending on the mediator, mass, and cross-section of interest, we study the dependence of the sensitivity on the latitude of the experiment.
Minerals are solid state nuclear track detectors - nuclear recoils in a mineral leave latent damage to the crystal structure. Depending on the mineral and its temperature, the damage features are retained in the material from minutes to timescales much larger than the age of the Solar System. The damage features from the fission fragments left by spontaneous fission of heavy unstable isotopes have long been used for fission track dating of geological samples. Laboratory studies have demonstrated the readout of defects caused by nuclear recoils with energies as small as ~1 keV. Using natural minerals, one could use the damage features accumulated over geological timescales to measure astrophysical neutrino fluxes (from the Sun, supernovae, or cosmic rays interacting with the atmosphere) as well as search for Dark Matter. Research groups in Europe, Asia, and America have started developing microscopy techniques to read out the nanoscale damage features in crystals left by keV nuclear recoils. The research program towards the realization of such mineral detectors is highly interdisciplinary, combining geoscience, material science, applied and fundamental physics with techniques from quantum information and Artificial Intelligence. In this talk, I will highlight the scientific potential of mineral detectors and briefly describe status and plans of the Mineral Detection of Neutrinos and Dark Matter (MDvDM) community.
The QCD axion is a compelling dark-matter candidate that also solves the strong CP problem using a Peccei-Quinn mechanism. The Axion Dark Matter eXperiment (ADMX) is the leading axion haloscope searching for dark matter in the micro-eV mass range favored by theoretical models. ADMX uses a single tunable resonant microwave cavity immersed in a magnetic field to look for the production of microwave photons as a result of the feeble coupling between the axion and electromagnetic fields. ADMX has excluded the detection of axions down to the benchmark Dine-Fischler-Srednicki-Zhitnitsky (DFSZ) model in the 2.6-4.2~$\mu$eV axion mass range over the past five years. As the experiment pursues higher axion masses, the complexity of the experiment increases due to the need to use arrays of smaller cavities to maintain DFSZ sensitivity to axion signals. In this talk I will summarize the most recent results and current status of the ADMX experiment, and discuss the plans to search for dark-matter axions with masses up to 20~$\mu$eV using multi-cavity arrays.
MADMAX, the MAgnetized Disc and Mirror Axion eXperiment, is a novel dielectric haloscope concept to detect the axion in the mass range 40-400 ueV through enhancement of the inverse Primakoff process. The discovery of the axion could solve both the strong CP problem, fundamental in particle physics, and the dark matter problem. In this talk, I will review the MADMAX design concept and discuss the status of ongoing research into the enhancing system for the weak axion signal. I will also discuss the first physics results from a prototype system called CB100 (Closed Booster 100 mm), operated for 3 weeks in CERN's 1.6T MORPURGO magnet in Spring 2023.
The axion is a hypothetical particle proposed to solve the so-called CP violation problem in strong interactions. If the axion exists, it could be intensively born inside the Sun, and then can be detected in the inverse reaction of resonance absorption by a $^7$Li-containing detector. A search for $^7$Li solar axions was performed with the Li$_2$MoO$_4$ low-temperature detectors of the AMoRE experiment. The data collected with 1.6 kg Li$_2$MoO$_4$ crystals over 11 months at the Yangyang Underground Laboratory (Y2L) in Korea can be used as a target and detector of axions with ~13% of detection efficiency. A detailed analysis procedure with the first results will be presented. Also, possibilities to reduce backgrounds will be discussed.
The Galactic Centre (GC) represents an intriguing playground for the astroparticle community where studying physical processes and testing theories and models. The complexity of such a region is evident at each wavelength of the electromagnetic spectrum: even at the shortest one the GC region assumes a key-role for understanding the nature and origin of the emission observed in γ-rays. The lack of a definitive explanation of such emission makes of the GC a privilegiate laboratory. SgrA — the SMBH located in the centre of the Milky Way — may be the favorite candidate to be the PeV-accelerator of cosmic-rays (CRs) in Our Galaxy. Or the evidence that the CR spectrum gets harder approaching the centre. Or the existence of still unobserved population of PWNe and SNRs. Or the decay/annihilation of Dark Matter are among the most plausible scenarios invoked to explain the measured gamma-ray emission. But the impact of systematics afflicting the data makes arduing to reach robust conclusions.
In view of the next generation experiments and observatories, a detailed analysis of several phenomenological models for the dubbed CR-Sea* — computed with DRAGON and GAMMASKY codes — is scrutinised in comparison with the observed spectra from the inner Galaxy. This study assumes a fundamental role in the analysis-chain of such data since represents the only method providing the background model for studying extended sources, as the Galactic Centre region, and characterizing its emission.
We provide a phenomenological description of the population
of galactic TeV Pulsar Wind Nebulae (PWNe) based on suitable assumptions for their space and luminosity distribution.
We constrain the general features of this population by
assuming that it accounts for the majority of bright sources
observed by H.E.S.S. Namely, we determine the maximal luminosity and fading time of PWNe by fitting the flux, longitude and
latitude distribution of bright sources in the Hess Galactic Plane Survey. This allows us to estimate the total luminosity and flux produced by galactic TeV PWNe. This also permits us to evaluate the cumulative emission from PWNe that cannot be resolved by H.E.S.S, showing that this contribution can be as alrge as $\sim 40\%$ of the total flux from resolved sources.
We argue that this is also relevant in the GeV domain providing a relevant contribution to the large-scale diffuse emission in the inner
Galaxy. Finally, the same result is obtained at PeV energy where the sum of the diffuse component due to unresolved PWNe and the truly diffuse emission well saturates the recent Tibet; data, without the need to introduce a progressive hardening of the cosmic-ray spectrum toward the Galactic center.
Thousands of GeV-emitters have been catalogued by now, with a great variety of object classes therein. A few systems appear particular suitable to probe Galactic cosmic rays, with studies typically revolving around particle acceleration in supernova remnants or pulsar wind nebulae. However, these systems evolve on time scales significantly longer than a human lifetime, virtually preventing the study of their time evolution of particle acceleration and losses. Conversely, we can use the variability induced by the changing conditions along orbits in binary systems or nova explosions to break model degeneracy. The short timescale variability can be used to unambiguously distinguish between leptonic and hadronic accelerators and identify the impact of processes beyond standard diffusive shock acceleration.
After 15 years of observations with the Fermi Large Area Telescope, we have tested particle acceleration in the time domain at GeV energies in a large variety of systems. This large dataset allowed us to break model degeneracy in shocks and jets, whether arising from relativistic or non-relativistic outflows, hence probing diverse conditions in a heterogeneous sample of binaries. In this talk, we will discuss what the observed GeV gamma-ray variability in eta Carinae, RS Ophiuchi and HESS J1832-093 can teach us about the underlying cosmic ray production in Galactic accelerators, and consider the implications for PeVatron searches.
Magnetars formed as a result of binary neutron star mergers are sources of multi-messenger emissions, in particular gravitational wave (GW), neutrino, and electromagnetic (EM) signatures. The physical model consists of a millisecond magnetar, whose rotation drives the pulsar wind nebula, and is surrounded by a kilonova ejecta. We discuss how this system acts as a source of high-energy cosmic rays, neutrinos and EM signatures from the ejecta. We find for our fiducial case of a magnetar at 10 Mpc the maximum all-flavor neutrino fluence is $\sim 0.07$ GeV/cm$^2$ at $\sim 10^8$ – $10^9$ GeV, which is beyond current IceCube’s limit for detection. Although the neutrino signatures from such individual systems may not be detectable, the stacking of observations in IceCube-Gen2 over $\sim 10$ years will enable us to detect the ultra-high energy neutrinos from such systems. Moreover, the next generation GW detectors will further help trigger such neutrino detections owing to their greater distance horizon. The EM signatures will potentially be seen in optical, X-ray and gamma-ray channels in the upcoming and existing EM telescopes.
In this work, we adopt KNe data to prepare a training, test, and validation data set to be fed into a conditional variational autoencoder to regenerate the KNe light curves for the required values of physical parameters. For different KNe models, the physical parameters governing the light curves are different based on the pre-merger or post-merger properties of the BNS merger event. We train the CVAE on the KNe data by conditioning the light curves on the physical parameters, with a training time of ~20 minutes, and rapidly generate light curves for the desired parameter values. Once the CVAE is trained and conditioned on the physical parameters, it takes ~1 milli-second to generate the light curves with a root mean square value of ~0.02 (AB mag) between the true and generated light curves, thus speeding up the process by ~1000 times as compared to the existing method. We have separately trained, generated, and verified the CVAE approach on two different KNe models, where one model is based on pre-merger while the other is on post-merger properties of BNS, and have obtained satisfactorily accurate results, with training time and light curves generating time of ~20 minutes and ~1 millisecond respectively while achieving a root mean square value of ~0.02 and 0.015 AB mag between the original and generated light curves for each model. This technique has the ability to provide an alternative to the time-consuming and resource-draining simulations.
In this contribution, we investigate the seasonal variation of multi-muon events, as observed by the NOvA Near Detector (ND) at Fermilab, using the general-purpose Monte Carlo code FLUKA, which simulates the transport and interaction of the air-shower particles in the atmosphere and other media. The upper atmosphere temperature suffers a seasonal variation over the year. Due to this phenomenon, an increasing flux of muons in summer over winter is expected, as observed for single muons, but not for multi-muon events, which presents an opposite seasonal variation. Our atmospheric model uses air densities for winter and summer calculated from the temperature and geopotential information at 37 pressure levels given by the European Center for Medium-Range Weather Forecasts (ECMWF) datasets in situ. Our FLUKA geometry model also considers a layered underground approximated to match the NOvA ND location. We compare our simulation results with the seasonal flux modulation of the multi-muon events detected by NOvA-ND. For the first time, we can quantitatively describe the multi-muon excess in winter over summer and obtain the dependence on the multi-muon event multiplicity observed by NOvA. Finally, we compare our results with the previous work from other authors based on CORSIKA simulations. We try to understand the reasons for the discrepancy by nearly a factor of four between the results of two Monte Carlo codes.
Cosmic rays (CRs) span a wide range of energies, where the ultra-high-energy CRs are studied through the extended air showers produced when CRs collide with the upper atmosphere on earth. The determination of their mass and energy depends upon the measured and simulated maxima air-shower profiles. These are modeled using hadronic Monte Carlo (MC) simulations. However, the measurements of diffractive signatures in proton-ion collisions substantially differ from the prediction of MC simulations. A short run of proton-oxygen (pO) collisions is planned at the Large Hadron Collider (LHC) at CERN in 2024 to improve the modeling of CR interactions and reduce the model uncertainties of proton-air cross-sections. While the inelastic cross-section will be measured directly, an array of very forward proton and neutron detectors introduced by the ATLAS and CMS experiments can provide a unique opportunity to study elastic and diffractive interactions in pO collisions at the center of mass energies above TeV. In my talk, I will present the possible impact of proton and neutron tagging on the measurement of the elastic and diffractive components and discuss the perspectives of measuring decay products of oxygen ions after dissociation during the preceding oxygen – oxygen run at the LHC using the array of very forward detectors.
Astrophysical neutrinos play an important role in modern multi-messenger astrophysics. They can be used to learn about the properties of their astrophysical origin but also to study and probe particle physics beyond the Standard Model not accessible in ground based laboratories, especially due to their high energy.
In this talk we consider a new light scalar field which mediates neutrino-neutrino interactions and thus turns the Universe partially opaque for them by increasing the likeliness to scatter with relic neutrinos of the cosmic neutrino background when traveling through space. By studying the magnitude of absorption for neutrinos coming from the two extra galactic sources identified so far by IceCube, namely NGC 1068 and the blazar TXS 0506+056, we can put limits on the coupling strength and the mediator mass which, as we show, significantly increase if the lightest neutrino is massless.
The work we present here is based on arXiv:2304.08533.
We calculate a new generation of Standard Solar Models (B22-SSMs) that implement state-of-the-art constitutive physics and updated sets of solar surface abundances, like e.g. those presented by Amarsi & Grevesse 2021 (AAG21) and by Magg, Bergemann et al. 2022 (MB22).
We compare the new SSMs predictions with helioseismic data and solar neutrino results and we also discuss the implications of the recent measurement of CNO neutrino signal performed by Borexino.
We show that MB22 abundances substantially alleviate the so-called solar composition problem, i.e. the the puzzling mismatch between the helioseismic constraints and SSMs prediction arisen in the early 2000s that had defied all attempted solutions in the form of non standard stellar physics.
After a brief introduction to neutrino electromagnetic properties, I will focus on the correlation between neutrino magnetic moment and neutrino mass mechanism. Then I will discuss that the models that induce large neutrino magnetic moments while maintaining their small masses naturally also predict observable shifts in the charged lepton anomalous magnetic moment by showing that the measurement of muon g−2 by the Fermilab experiment can be an in-direct and novel test of the neutrino magnetic-moment hypothesis, which can be as sensitive as other ongoing-neutrino/dark matter experiments. The promising new possibilities for probing neutrino electromagnetic properties in future experiments from terrestrial experiments and astrophysical considerations will also be discussed. This talk will be based on results obtained in hep-ph 2203.01950, 2007.04291, 2104.03291, and 2204.XXXX.
The IceCube Neutrino Observatory is uniquely sensitive to the MeV neutrinos emitted during a core-collapse supernova, with potential applications beyond supernovae. This talk will describe an analysis stream that can be used to respond to external alerts, such as those originating from the Ligo-Virgo-Kagra detector for gravitational waves. Additionally, we will demonstrate the versatility of this low-energy data stream by discussing the search of MeV neutrinos coincident with GRB 221009A, where neutrino emission can occur through a variety of mechanisms, such as core-collapse supernovae or neutrino-dominated accretion flows.
We developed a new analysis method for supernova model identification using supernova neutrino observations in Super-Kamiokande (SK). Our new method uses some information on late-phase neutrinos observed in SK, such as the duration time of neutrino observation and averaged neutrino energy. In this presentation, we report the evaluation results of the supernova model identification performance.
The IceCube Neutrino Observatory is a Cherenkov detector instrumenting over a cubic kilometer of Antarctic ice. The main IceCube array can detect high-energy neutrino emissions from astrophysical sources, while the denser-configured subdetector (DeepCore) can observe down to GeV-scale neutrinos, which improves the sensitivity to measure the disappearance of atmospheric muon neutrinos. For precise and rapid reconstructions, machine-learning techniques are employed. This talk presents a new measurement of $\Delta m^2_{32}$ and $\sin^2(\theta_{23})$ using 9.3 years of atmospheric neutrino data compared to existing results from other experiments.
The ICARUS detectors have proven the effectiveness of LArTPC technology with a successful three-year long run at INFN-LNGS, establishing the power of a liquid argon detector on a neutrino beam. Currently, ICARUS-T600 is collecting data at Fermilab Booster Neutrino Beam in the SBN program. A light detection system, based on PMTs deployed behind the TPC wire chambers, is in place to detect vacuum ultraviolet photons produced by ionizing particles in LAr. This system is fundamental for the detector operation, providing an efficient trigger and contributing to the 3D reconstruction of events. Moreover, since the TPC is exposed to a huge flux of cosmic rays due to its operation at shallow depths, the light detection system allows for the time reconstruction of events, contributing to the identification and to the selection of neutrino interactions within the beam spill gates.
This contribution will primarily focus on the cosmic track-light coincidences analysis, and the neutrino interaction selection, with an overview of the current analysis status and its first results.
The IceCube Upgrade is an extension of the IceCube neutrino telescope aiming to better detect atmospheric neutrinos down to a few GeV. It will consist of 7 additional strings instrumented with more than 100 newly developed optical modules each. More than 600 of these additional optical sensors will be embedded in almost 3 Mt of the most transparent ice. The denser module spacing in combination with the multi-pmt instrumentation of the new modules is expected to improve the energy as well as the directional resolution of the detector. In addition, the new instrumentation will increase the detection efficiency for GeV-scale neutrino interactions. In this talk, we present the IceCube Upgrade sensitivities to atmospheric neutrino oscillations as well as the neutrino mass ordering.
The flavor composition of high-energy neutrinos carries important information about their birth. However, the two most common production scenarios, $pp$ and $p\gamma$ collisions, lead to the same flavor ratio when neutrinos and antineutrinos are indistinguishable. The Glashow resonant interaction $\bar{\nu}_e+e^- \rightarrow W^-$ becomes a window to differentiate the antineutrino contribution from the total diffuse neutrino flux, thus lifting this degeneracy. In this talk, I will discuss the power of Glashow resonant events in measuring the fraction of the $\bar{\nu}_e$ flux with current IceCube data, and the projected sensitivities based on the combined exposure of next-generation Cherenkov neutrino telescopes around the globe.
Heavy Neutral Leptons (HNLs) are sterile neutrinos posited as an explanation for light neutrino masses. IceCube is uniquely capable of searching for an HNL in the hundreds of MeV to single GeV range by looking for atmospheric tau neutrinos upscattering to HNLs in the detector. The HNLs produced in IceCube would decay quickly, leading to Cherenkov radiation in both production and decay separated by a few meters, producing a “double cascade” signature in the detector. A simulation based on the most up-to-date calculations of HNL decay modes and cross-sections is required to understand the hundreds of MeV to single GeV parameter space for an HNL search. This talk outlines the capabilities of the first HNL simulation for neutrino observatories, and presents sensitivities for IceCube’s HNL search.
Since 1983 the Italian groups collaborating with Fermilab (US) have been running a 2-month summer training program for Master students. While in the first year the program involved only 4 physics students, in the following years it was extended to engineering students. Many students have extended their collaboration with Fermilab with their Master Thesis and PhD.
The program has involved almost 600 Italian students from more than 20 Italian universities. Each intern is supervised by a Fermilab Mentor responsible for the training program. Training programs spanned from Tevatron, CMS, Muon (g-2), Mu2e and SBN and DUNE design and data analysis, development of particle detectors, design of electronic and accelerator components, development of infrastructures and software for tera-data handling, research on superconductive elements and accelerating cavities.
In 2015 the University of Pisa included the program within its own educational programs. Summer Students are enrolled at the University of Pisa for the duration of the internship and at the end of the internship they are write summary reports on their achievements. After positive evaluation by a University Examining Board, interns are acknowledged 6 ECTS credits for their Diploma Supplement. In the years 2020 and 2021 the program was canceled due to the sanitary emergency but in 2022 it was restarted and allowed a cohort of 21 students to be trained for nine weeks at Fermilab. We are now organizing the 2023 program.
This project aims at developing a low-cost open-hardware alternative to commercial temperature controllers with parts costing less than 100U$S that meets the performance parameters for diverse applications. As a demonstrator, we used a 40W output power version to regulate the temperature at (130+/-0.5)K in different scientific CCD testing stations equipped with cryocoolers with unregulated cooling capacity. The heating power is set by a PID algorithm that reads the temperature using a PT-100 and an analog-to-digital converter. The controller is powered by a Raspberry Pi Pico, and the status is displayed on an OLED screen. Both hardware and software are modular, making them easily scalable to new capabilities. PCB fabrication files, schematics, and firmware-client software are available in a public repository. Building, implementing, and assessing the controller performance in the laboratory is an ideal project for undergraduate students who wish to learn instrumentation techniques and new skills such as PCB design, SPI/I2C communication protocols, python and multi-thread programming, serial communication, soldering, electronics, etc.
The KM3NeT neutrino detectors are currently under construction at two locations in the Mediterranean Sea and starting to produce valuable data both for the astrophysics and neutrino physics communities. Having committed itself to an Open Science policy, the KM3NeT collaboration is establishing a system to facilitate data sharing, open software development and integration of KM3NeT analyses in common analysis platforms, as well as providing training material. In this contribution, the current prototype architecture and future development initiatives are presented.
Public event
Further details at
https://taup2023.hephy.at/public-events/
By building enormous experiments in unusual locations: deep under-ground, under-water or under-ice, on mountains, in large uninhabited areas or in satellites, scientists have determined a clear picture of how the Universe has evolved since the Big Bang. But there are still large unanswered questions. What is the Dark Matter that permeates our Galaxy with 5 times more mass in the dark spaces than in the stars? Why is the Universe dominated by matter with little anti-matter left over after the Big Bang? What are the details of the mysterious Black Holes observed throughout the universe? What are the properties of the enigmatic neutrino particles? By studying particles and waves from outer space scientists are adding to our understanding of the Universe from the smallest particles to the largest scales.
In this talk we will discuss the state of the art on our theoretical understanding of the Galactic cosmic ray physics in connection with the latest data collected by space-based experiments. Emphasis will be put on energies from about 100 MeV up to TeV. We will present the most relevant open problems in the nuclear and in the leptonic sector, and will discuss discovery potentials in the ani-matter sector.
The study of Ultra-High-Energy Cosmic Rays (UHECR) has dramatically changed in the last 20 years with the advent of the Pierre Auger Observatory and the Telescope Array project. Before the precision of these instruments, there was high uncertainty in whether the UHECR flux dramatically cuts off above 50 or so EeV; now, the cutoff is verified fact, and the details of the spectrum show features begging for astrophysical interpretation. Before their sensitivity, there was a relatively simple expectation of proton domination above an EeV; now, UHECR composition is known to be a rich blend of atomic nuclei that show a complex evolution with energy. Before their shear scale, the isotropy of the data begged the question of whether sources could ever be pinpointed; now, we have discovered large-scale anisotropies and are inching closer to the clear association of the highest energy UHECR with promising source classes. As exciting as these changes have been, the recent hints and observations in UHECR physics- muon excesses, mass anisotropies, spectrum/mass correlations- show promise toward leading again to considerable modifications in how we see the highest energy end of the particle universe. This talk will present the most current picture of the field and then use the current status to frame where UHECR physics is going over the next 10 to 20 years.
Our mission at the Sanford Underground Research Facility (SURF) is to advance world-leading science and inspire learning across generations. In this presentation, I will discuss the various ways in which we inspire learning, especially through public events and K-12 programming and how we work to make our activities accessible to a broader audience. I’ll touch on specific events that engage learners of all ages, how virtual reality and augmented reality can be used to expand our outreach efforts, and what is coming in the future for SURF.
With my talk, first, I would like to review the current status of leading deep underground laboratories worldwide. Major experimental facilities would be updated. And I would like to give more importance to new developments going on in those laboratories. I will try to cover new techniques in low radioactivity measurements, new equipment, etc.
In addition to these main topics, I will add multidisciplinary research underground, which is pursued in some laboratories, Biology, Geology, Environmental radioactivity measurements, R&D with semiconductor industries, etc.
This is the first town hall meeting of the Initiative for Dark Matter in Europe and beyond (iDMEu), a JENA (Joint ECFA-NuPECC-APPEC) activity to bring together researchers from different communities searching for dark matter.
It takes place on the last day of the XVIII International Conference on Topics in Astoparticle and Underground Physics (TAUP2023), at the University of Vienna and online on Zoom.