We investigate the effect of inertial range magnetohydrodynamic turbulence to the 1-dimensional force-field model. Using well established quasilinear theory together with the recently available magnetic power spectrum from Parker Solar Probe, we perform calculations of parallel diffusion coefficient, modulation potential and galactic cosmic ray flux in the inner heliosphere. The model applies...
Complex Dark Sectors are theories of hidden particles and forces that could constitute all or part of dark matter but have non-minimal interactions between them, such as dark analogues of electromagnetism of the strong force. These scenarios are predicted by many highly motivated extensions of the Standard Model that solve fundamental mysteries like the hierarchy problem, but are notoriously...
An intriguing possibility for dark matter is that it formed bound states in the early Universe, in a scenario called 'composite' dark matter, much like the Standard Model fundamental particles formed nucleons, nuclei and atoms. One of the simplest composite dark matter models consists of dark fermions bound together by a real scalar field. Composite states that are massive enough source scalar...
The Hubble-Lemaitre tension is currently one of the most important questions in cosmology. Most of the focus so far has been on reconciling the Hubble constant value inferred from detailed cosmic microwave background measurement with that from the local distance ladder. This emphasis on one number -- namely H0 -- misses the fact that the tension fundamentally arises from disagreements of...
The detailed measurement of the daily electron, positron, proton, and helium fluxes based on 10 year data from May 20, 2011 to May 2, 2021 with the Alpha Magnetic Spectrometer on the International Space Station, is presented.
The origin of the cosmic rays (CRs) is a complex problem that requires a proper understanding of the CR's acceleration, diffusion, and radiation mechanisms. However, observations suggest that these properties of CRs depend highly on the initial supernova explosion conditions and the structure of the ambient material into which a supernova remnant (SNR) expands. Therefore, a source-by-source...
Most of the volume of the Universe consists of the Intergalactic Medium (IGM), space between collapsed structures like galaxies and galaxy clusters. Extragalactic photons and charged particles that propagate through the Universe spend most of their time in the IGM and can be influenced by its properties. In this talk, I will present a few examples of how we can study fundamental physics from...
Cosmic Rays (CR) inside the Heliosphere interact with the solar wind and with the interplanetary magnetic field, resulting in a temporal variation of the cosmic ray intensity near Earth for rigidities up to few tens of GV. This variation is known as Solar Modulation. Previous AMS results on proton and helium spectra showed how the two fluxes behave differently in time. To better understand...
The addition of spatial dimensions compactified to submillimeter scales serves as an elegant solution to the hierarchy problem. As a consequence of such large extra dimensions, is the possibility of producing primordial black holes (PBHs) from high-energy collisions in the early universe, leading to a novel source of dark matter. While four-dimensional PBHs have been extensively studied, they...
We present a novel statistical framework to infer cosmological parameters from cosmological surveys, based on a Bayesian forward modelling of correlated Poisson processes. In particular, given catalogs of galaxies and standard sirens, we compute the posterior distributions for cosmological parameters by assuming that the detection of standard sirens follow a spatial Poisson process that...
With the successful detection of cosmic high-energy neutrinos and the first high-probability association of such a neutrino to the blazar TXS 0506+056 leads to the anticipation that active galactic nuclei could soon be identified as point source emitters of high-energy neutrinos. This opens up new challenges for a joint explanation of the observed electromagnetic spectrum together with...
Magnetic monopoles and Q-balls are examples of topological and nontopological solitons, respectively. A new soliton state with both topological and nontopological charges is shown to also exist, given a monopole sector with a portal coupling to an additional scalar field S with a global U(1) symmetry. This new state, the Q-monopole-ball, is more stable than an isolated Q-ball made of only S...
The Cryogenic Underground Observatory for Rare Events (CUORE) is the first bolometric experiment searching for 0νββ decay that has been able to reach the one-tonne mass scale. The detector, located at the LNGS in Italy, consists of an array of 988 TeO2 crystals arranged in a compact cylindrical structure of 19 towers. CUORE began its first physics data run in 2017 at a base temperature of...
The era of multi-messenger astronomy began with the gravitational-wave detection of the binary neutron-star merger, GW170817, in coincidence with a short gamma-ray burst, GRB 170817A. One of its primary goals is a detection of another coincidence of gravitational and electromagnentic emission. With that in mind, we present a follow-up search for excess emission of gamma-rays with the Fermi...
Absorption and emission lines in the optical spectrum are typically used to investigate the presence of large-scale environments in active galactic nuclei. In BL Lac objects, this approach is hampered by the dominant non-thermal continuum of their relativistic jet, which prevents us from identifying the thermal emission of the photon fields produced by such large-scale structures.
However,...
The Galactic Center (GC) region has been intensively studied in gamma-rays in the past decades. Fermi LAT has discovered a GeV excess which is not fully understood, and the first detection of a PeVatron by H.E.S.S. indicates the existence of cosmic ray sources providing energies up to a PeV or higher. The emission of TeV gamma rays in the GC is affected by the source position and the...
The origin of IceCube astrophysical neutrinos is an important question in astrophysics and neutrino science, and the real-time follow-up of neutrino events in the very-high-energy (VHE, E > 100 GeV) gamma-ray band is a promising way to locate neutrino sources. In 2017, evidence was presented that a flaring gamma-ray blazar, TXS 0506+056, was in spatial and temporal coincidence with the...
A bright and statistically significant flux of GeV-scale gamma rays has been detected from the region surrounding the Galactic Center. While the spectrum, angular distribution, and intensity of this signal is consistent with the predictions of annihilating dark matter matter particles, it has also been suggested that these gamma rays could potentially be produced by a large population of...
The search for the PeVatrons is one of the most important goals of the very-high-energy gamma-ray community. Gamma-rays of energies >100 TeV are produced by particles previously accelerated to PeV energies in astrophysical sources and point back to them because they are not deflected by galactic magnetic fields. Last year, LHAASO published a list of 12 sources emitting gamma rays of energy...
As highly energetic physics laboratories, blazars are prime candidates to reveal the mysteries of the most energetic parts of our universe. For many of them, the very-high-energy (>0.2 TeV, VHE) γ-ray band as well as the X-ray bands are especially interesting since they host the most variable part of their emission.
We present a multiwavelength (MWL) data set of Mrk 501 obtained from 2017...
Galactic cosmic rays interact with the Sun’s atmosphere to produce gamma rays via pion decay up to at least 100 GeV. The role of solar magnetic fields in modulating and enhancing the flux of these gamma rays is not completely understood, and can be further elucidated with a broadband spectrum extending into the TeV range. The HAWC observatory is a ground-based array of photo-detectors...
I present a new, open-source, pure Python program, MUTE (MUon inTensity codE) (A. Fedynitch, W. Woodley, M.-C. Piro 2022 ApJ 928 27). MUTE combines the state-of-the-art codes MCEq (Matrix Cascade Equation) and PROPOSAL (PRopagator with Optimal Precision and Optimised Speed for All Leptons) to compute the cosmic ray cascades in the atmosphere and the propagation of muons through matter in...
The Galactic Center Excess (GCE) remains one of the most intriguing discoveries from the Fermi Large Area Telescope (LAT) observations. I will revisit the characteristics of the GCE by using a new set of high-resolution galactic diffuse gamma-ray emission templates. This diffuse emission, which accounts for the bulk of the observed gamma rays, is ultimately due to cosmic-ray interactions with...
The origins of the GeV gamma-rays from nearby radio galaxies are unknown. Hadronic emission from magnetically arrested disks (MADs) around central black holes (BHs) is proposed as a possible scenario. Particles are accelerated in the MAD by magnetic reconnection and stochastic turbulence acceleration. We investigate the feature of the radio galaxies that can be explained by the MAD model. We...
The origin of Galactic cosmic rays (CR) is still a matter of debate. Supernova remnants (SNR) remains the best candidates thanks to their kinetic luminosity and a well studied acceleration mechanism, the diffusive shock acceleration, which has been shown to efficiently work at the SNR forward shocks. However, recently their ability to accelerate particles up to PeV energies, as required from...
Particle pre-acceleration remains an important unresolved problem in the diffusive shock acceleration (DSA) theory. This mechanism acting at merger shocks in galaxy clusters is thought to produce relativistic electrons that form the so-called radio relics detected in radio and X-ray. DSA at merger shocks may also generate high- and ultra-high-energy cosmic rays and associated gamma-ray...
At the highest energies, the neutrino nucleon cross-section $\sigma$ can only be measured via interaction of ultrahigh energy (UHE) neutrinos with target particles in the Earth. The energies involved ($E_{\nu} \geq 10^{16}$ eV) probe $\sqrt{s}$ higher than anything possible at current colliders. Measurement of $\sigma$ at these energies will directly probe new physics models. Many current and...
Experimental observations have demonstrated a strong correlation between star-forming processes and gamma-ray luminosities. However, the very nature of these emissions is still under debate. Certainly, star-forming and starfurst galaxies (SFGs and SBGs) are well-motivated astrophysical emitters of gamma-rays and neutrinos through hadronic collisions. In this talk, I will present several...
Dark matter at the keV scale has become an active topic in the last decade. The NuSTAR x-ray observatory, with its energy bandpass 3--150 keV and wide-angle aperture for unfocused x-rays, is an ideal platform to search for decaying keV-scale dark matter, e.g. sterile neutrinos. Previous NuSTAR analyses constrained much of the sterile-neutrino parameter space for masses ~10--40 keV, improving...
The detection of ultra-high-energy neutrinos, with energies above 100 PeV, is requisite to fully understand the high-energy Universe. Their discovery might soon be within reach of upcoming neutrino telescopes, yet in-depth discovery forecasts for their astrophysical sources are largely unavailable. We present a robust framework to compute the statistical significance of source discovery via...
We present high statistics measurements of the secondary cosmic rays Lithium, Beryllium, Boron, and Fluorine based on 10 years of AMS data. The properties of the secondary cosmic ray fluxes and their ratios to the primary cosmic rays Li/C, Be/C, B/C, Li/O, Be/O, B/O, and F/Si are discussed. The systematic comparison with the latest GALPROP cosmic ray model is presented.
We propose a novel mechanism of boosting dark matter by cosmic-ray neutrinos. The new mechanism is so significant that the arriving flux of cosmic-ray neutrino boosted dark matter (νBDM) lighter than O(1) MeV on Earth substantially larger than the one of the cosmic-ray electron boosted dark matter. Therefore, νBDM can dominantly contribute in direct detection experiments. We derive...
The measurement of high-energy neutrino-matter interactions furthers our knowledge of nucleon structure and allows us to test proposals beyond the Standard Model: the higher the energy, the more piercing the probe. Ultra-high-energy (UHE) cosmic neutrinos, with EeV-scale energies (1 EeV = 10^{18} eV), offer the ultimate high-energy probes of neutrino physics. For fifty years, they have evaded...
We present high statistics measurements of cosmic H, He, Li and Be isotopes based on 10 years of AMS data.
Gamma-ray observations of extreme astrophysical transient phenomena continue to play an important role in understanding both the physical emission mechanisms in these sources and their contribution to the cosmic-ray population. One transient class that continues to expand, but remains difficult to understand, are Fast Radio Bursts (FRBs). Due to their sporadic and short-lived emission (~ms),...
The Large-Sized Telescopes (LSTs) of the Cherenkov Telescope Array (CTA) are designed to maximize the performance of gamma-ray studies for low energies, rapid telescope re-pointing, large field of view, and unprecedented flux sensitivity. The LST will dominate the performance of the CTA Observatory between 20 GeV and 150 GeV. The prototype of the LST telescopes (LST-1) was inaugurated in 2018...
The IceCube Neutrino Observatory has sensitivity to sterile neutrino oscillations through matter-enhanced oscillation occurring in the few TeV energy range for eV$^{2}$-scale mass-squared splittings. I will present previous measurements of these effects in $\nu_\mu$ disappearance, which has strong sensitivity to the mixing angle $\theta_{24}$ via $\bar{\nu}_\mu\rightarrow\bar{\nu}_s$...
We present high statistics measurements of primary cosmic rays from Proton to Iron based on 10 Years AMS data. The properties of primary cosmic ray fluxes are discussed. The systematic comparison with the latest GALPROP cosmic ray model is presented.
The direct detection of sub-GeV dark matter interacting with nucleons is hampered by the low recoil energies induced by scatterings in the detectors. This experimental difficulty is avoided in the scenario of boosted dark matter where a component of dark matter particles is endowed with large kinetic energies. In this talk, I will show that the current evaporation of primordial black holes...
Beyond the Standard Model (BSM) interactions in the neutrino sector have been of much interest in cosmology and astroparticle physics. We developed a Monte Carlo code to investigate the neutrino time delay distribution caused by BSM interactions en route to the observer. While we find excellent agreement for small optical depths, the optically thick limit show features that are not described...
We present first results of the commissioning data of two Single-Mirror Small-Sized Telescopes (SST-1M) for detection of gamma rays with the imaging air Cherenkov technique. SST-1M adopts a Davies-Cotton optics and a fully digitising silicon photomultipliers (SiPM) based camera. SST-1M telescopes have a lightweight and compact structure with 4 m-diameter mirror dish composed of 18 hexagonal...
Cosmic Nitrogen, Sodium, and Aluminum nuclei are a combination of primaries, produced at cosmic-ray sources, and secondaries resulting from collisions of heavier primary cosmic rays with the interstellar medium. We present high statistics measurements of the N, Na and Al rigidity spectra. We discuss the properties and composition of their spectra and present a novel model-independent...
Strong gravitational lensing provides a promising way to look for clues to the elusive particle nature of dark matter. Indeed, subtle perturbations to lensed images can reveal the dark-matter distribution on sub-galactic scales. In addition to the subhalos of the main lens, a significant contribution to these perturbations comes from dark matter halos along the line-of-sight between the...
We emphasize the distinctive cosmological dynamics in multi-component dark-matter scenarios and its impact in probing a sub-dominant component of dark matter.
The dynamics originates from the conversion among different dark-matter components.
We find that the temperature of the self-interacting sub-component dark matter is significantly enhanced by the dark-matter annihilation into the...
The AMS-02 experiment has provided high-precision measurements of several cosmic-ray (CR) species. I plan to review the implication of the CR measurements of antiprotons, protons, helium, helium 3, boron, carbon, nitrogen, and oxygen. The achieved percent-level accuracy allows us, for example, to investigate different CR propagation scenarios or to study the universality of CR acceleration, a...
Neutrinos remain mysterious. As an example, enhanced self-interactions (νSI), which would have broad implications, are allowed. At the high neutrino densities within core-collapse supernovae, νSI should be important, but robust observables have been lacking. We show that νSI make neutrinos form a tightly coupled fluid that expands under relativistic hydrodynamics. The outflow becomes either a...
The isothermal Jeans model is a semi-analytical approach to modelling galaxies and galaxy clusters with self-interacting dark matter (SIDM) that has been shown to work remarkably well. Recent studies have found great success testing Jeans model predictions for SIDM halos against both observations and simulations while assuming spherical symmetry. In the presence of baryons SIDM halos are known...
The High Energy cosmic-Radiation Detection (HERD) facility is one of several space astronomy payloads onboard the future Chinese Space Station (CSS), planned for operation starting around 2027 for about 10 years. HERD is a China-led mission with key European contributions led by Italy. The primary scientific objectives of HERD are: Indirect dark matter search with unprecedented sensitivity;...
Strongly-lensed galaxies are a unique laboratory for probing dark matter substructure and testing the fundamental assumptions of the ΛCDM paradigm. However, the statistical difficulties with analyzing such observations are formidable, requiring disentangling the source galaxy’s light from the lens’ mass distribution and marginalizing over different substructure configurations. In this talk I...
Low mass fast moving/energetic dark matter (DM) is very well motivated and has been a subject of attention in the literature. These fast-moving particles can gain enough kinetic energy to pass the thresholds of some Large volume terrestrial detectors. For instance, fast-moving or "boosted" DM can account for the recent excess in electron recoil events observed by the XENON1T detector, due to...
We present the first results of the ERC PeVSPACE project, aimed at fundamentally improving the precision of direct cosmic ray measurements at the highest energies – in the TeV–PeV range, on DArk Matter Particle Explorer (DAMPE) and High Energy Radiation Detector (HERD) experiments.
DAMPE and HERD provide a unique opportunity of directly probing cosmic ray spectra close to the “knee”....
The NEWS-G direct dark matter search experiment uses spherical proportional counters (SPC) with light noble gasses to explore low WIMP masses. The current iteration of the experiment consists of a large 140 cm diameter SPC installed at SNOLAB with a new sensor design, and lots of improvements in detector performance and data quality. Before its installation at SNOLAB, the detector was operated...
The IceCube Neutrino Observatory has been observing a diffuse flux of high-energy astrophysical neutrinos in multiple detection channels since 2013. These detection channels are complementary with respect to event topologies such as muon tracks and cascades, the sensitive energy range, and backgrounds. In this analysis we combine two of these channels, through-going muon tracks and contained...
The origin of the large-scale magnetic fields in the Universe is one of the long-standing problem in cosmology. To discriminate among the different explanations it is crucial to measure the intergalactic magnetic field (IGMF) in the voids among the galaxies. Gamma-rays coming from extragalactic sources can be used to constrain the IGMF due to their interaction with the intergalactic medium....
The latest results from DEAP-3600 will be presented, including the best constraints on TeV-scale mass dark matter scattering in argon, and world-leading constraints on Planck-scale mass dark matter. DEAP-3600 is located at SNOLAB, 2 km underground in Sudbury, Ontario. This spherical detector consists of 3.3 tonnes of liquid argon in a large ultralow-background acrylic cryostat instrumented...
We are observing extensive air showers using the Tibet-III air shower array and the undergound water-Cherenkov Muon Detector array (MD) to measure the chemical composition of cosmic rays around the knee energy region. We have developed a method to select air showers induced by primary protons with the energy between 40 TeV and 630 TeV by using the number of muons detected by the MD in each...
Parton showers are part and parcel of particle phenomenology, but what in the case of a confining dark sector with no light quarks below the confinement scale? Then the only available hadronic states are ‘glueballs’, composite gluon states. To date, there have been very few quantitative studies of dark shower signatures with glueball final states, despite the fact they commonly appear in...
The Technical Design of the DarkSide-20k experiment has been finalised and the detector construction in the Gran Sasso National Laboratory in Italy starts this year. The experiment is designed to observe WIPMs scattering from argon atoms in 20 tonnes of the liquid argon target. Scintillation light generated during the interaction is detected by planes of Silicon photomultipliers (SiPMs). The...
The IceCube Neutrino Observatory has been observing a diffuse astrophysical neutrino flux, measuring the energy spectrum and flavor composition in different detection channels. With about 10 years of data, we combine the detection channels focused on the event topologies of tracks and cascades to measure the energy spectrum and flavor composition with improved precision compared to the...
Darkside-20k will exploit the physical and chemical properties of liquid argon housed within a large dual-phase time project chamber (TPC) in its direct search for dark matter. The TPC will utilize a compact, integrated design with many novel features to enable the 20t fiducial volume of underground argon. Underground argon (UAr) is sourced from underground CO2 wells and depleted in the...
Warm dark matter (WDM) could explain some small-scale structure observations that have challenged the cold dark matter (CDM) model, as warm particles suppress structure formation due to free streaming effects. Observing small-scale structure thus provides a valuable way to distinguish between CDM and WDM. In this talk, I will present a semi-analytical model of the dark matter substructure...
Astrophysical neutrinos are an important piece of the TeV multimessenger astrophysics puzzle. However, the significant background of atmospheric neutrinos seen in our neutrino observatories makes it difficult to study neutrino sources below 100 TeV in the southern sky Looking for starting events from the southern sky with IceCube allows us to reject not only events from incoming atmospheric...
The Alpha Magnetic Spectrometer collected over 150 billion cosmic rays events during the first 8.5 years of operation aboard the International Space Station. A component of Z>2 ions with rigidities below the rigidity cutoff and located in the South Atlantic Anomaly have been measured both in the down-going and up-going direction.
Galactic PeVatrons are astrophysical sources accelerating particles up to a few PeV ($\sim$10$^{15}$ eV). The primary identification of both electron and proton PeVatrons is gamma-ray radiation at ultra-high energies (UHE, E$>$100 TeV). Recently, LHAASO detected 14 steady gamma-ray sources with photon energies above 100 TeV and up to 1.4 PeV. Most of these sources contain possible source...
We are going to present the CYGNO/INITIUM project, an experiment that emerges as a new approach for directional Dark Matter searches using a gaseous TPC with the purpose of detecting low mass (0.5-50 GeV) WIMPS and performing solar neutrino spectroscopy. This project distinguishes itself by the use of He:CF$_4$, a low-density gas mixture sensitive to both spin dependent and independent...
LHAASO J2108+5157 is the first gamma-ray source directly discovered in the Ultra-High-Energy band by the LHAASO collaboration. Two molecular clouds identified in the direction towards LHAASO J2108+5157 make the source a promising galactic PeVatron candidate. In 2021, the Large-Sized Telescope prototype (LST-1) of the Cherenkov Telescope Array (CTA) Observatory performed observations of LHAASO...
The PICO collaboration searches for WIMPs using large superheated liquid detectors, or bubble chambers. Recent results from the complete exposure of the PICO-60 C$_3$F$_8$ detector at SNOLAB set the world’s most stringent limits on WIMP-proton spin-dependent interactions. I will present the current status of the construction and physics potential of the next generation, tonne-scale experiment...
Thermal electrons cannot directly participate in the process of diffusive acceleration at electron-ion shocks because their Larmor radii are smaller than the shock transition width: this is the well-known electron injection problem of diffusive shock acceleration. Instead, an efficient pre-acceleration process must exist that scatters electrons off of electromagnetic fluctuations on scales...
The SENSEI Experiment leads the direct-detection searches for sub-GeV dark matter (DM) using the novel Skipper-CCD sensors. The Skipper-CCDs can provide repetitive non-destructive readouts of a single pixel’s charge reducing the noise to a negligible level and reaching a single electron distinction.
Already with the small-scale prototype runs, SENSEI achieved the lowest rates in silicon...
The supernova remnant SNR G106.3+2.7 in the proximity of the Boomerang PWN has recently gained a lot of attention due to the emission above 100 TeV detected by HAWC, Tibet ASγ, and LHAASO. This SNR shows a characteristic comet-like morphology in radio observations, with a head and a tail. Due to the limited angular resolution of air shower experiments, it is not clear if the emission comes...
Axion-like particles (ALPs) are a well-motivated candidate for constituting a significant fraction of dark matter. They are produced in high-energy environments, such as core-collapse supernovae (CCSNe), and could undergo conversion into gamma-rays in the presence of an external magnetic field, with a characteristic spectrum peaking in the 30--100-MeV energy range. CCSNe are often invoked as...
The Pacific Ocean Neutrino Experiment (P-ONE) is a proposed cubic kilometre class neutrino telescope two hundred kilometres off the coast of Vancouver Island, Canada. A partnership with Ocean Network Canada (ONC) brings extensive knowledge, experience, and infrastructure to build a novel large-scale neutrino telescope in the ocean. P-ONE's primary scientific goals are to advance the field of...
Precision measurements of cosmic ray positrons are presented up to 1.4 TeV based on 3.4 million positrons collected by the Alpha Magnetic Spectrometer on the International Space Station. The positron flux exhibits complex energy dependence. Its distinctive properties are: (a) a significant excess starting from 24.2 GeV compared to the lower-energy, power-law trend; (b) a sharp drop-off above...
Axion-like particles (ALPs) decaying before the time of recombination can have
strong implications in a range of cosmological and astrophysical observations. In this
talk I present a global analysis of a model of decaying ALP, focusing specifically on their
coupling to photons. Exploiting the multidisciplinary nature of the GAMBIT frame-
work, we combine state-of-the-art calculations of...
Latest results by AMS on the fluxes and flux ratios of charged elementary particles in the absolute rigidity range from 1 up to 2000 GV reveal unique properties of cosmic charged elementary particles. In the absolute rigidity range ~60 to ~500 GV, the antiproton flux and proton flux have nearly identical rigidity dependence. This behavior indicates an excess of high energy antiprotons compared...
W50/SS433 is a complex and fascinating system that represents an important test bed for many astrophysical processes. Powered by the microquasar SS 433, the W50 nebula — classified as a supernova remnant with an unusual double-lobed morphology reminiscent of a Manatee — has been proposed to be a Galactic PeVatron candidate; a scenario that has been recently revived with the detection of very...
The SABRE (Sodium iodide with Active Background REjection) experiment aims to detect an annual rate modulation from dark matter interactions in ultra-high purity NaI(Tl) crystals in order to provide a model independent test of the signal observed by DAMA/LIBRA. It is made up of two separate detectors; SABRE South located at the Stawell Underground Physics Laboratory (SUPL), in regional...
In this talk, I will evaluate the potential for gravitational-wave (GW) detection in the frequency band from 10 nHz to 1 $\mu$Hz using extremely high-precision astrometry of a small number of stars. In particular, I will argue that non-magnetic, photometrically stable hot white dwarfs (WD) located at $\sim$ kpc distances may be optimal targets for this approach. Previous studies of astrometric...
After almost two decades of searches, in January 2019, MAGIC unambiguously detected TeV emission from the gamma-ray burst GRB 190114C. This long-awaited detection marked the beginning of the very high energy (VHE, $E>100$ GeV) era for GRB studies. After this historical achievement, the MAGIC collaboration continued its effort in the follow-up of GRBs. In December 2020, MAGIC detected GRB...
If the dark matter annihilation cross section is velocity dependent, the dark matter pair-wise relative velocity distribution enters into the calculation of the annihilation signals and the so-called J-factors. Studies of velocity-dependent dark matter annihilation commonly rely on simplified analytic models for the dark matter phase space distribution, which need to be tested against...
Dark matter (DM) particles are predicted to decay into Standard Model particles which would produce signals of neutrinos, gamma-rays, and other secondary particles. Neutrinos provide an avenue to probe astrophysical sources of DM particles. We review the decay of dark matter into neutrinos over a range of dark matter masses from MeV/c2 to ZeV/c2. We examine the expected contributions to the...
Gamma-ray burst (GRB) emission in the very high energy (VHE, E>100GeV) band has been discussed and theorized for many years, but has eluded for a long time the observations. Only in the last years the Cherenkov telescopes MAGIC and H.E.S.S. have unequivocally proven that VHE GRB afterglow radiation is produced up to a few TeV for at least a (sub-)class of GRBs. This newly opened TeV spectral...
TeV halos have become a new class of astrophysical objects which were not predicted before their recent observation. They offer evidence that diffusion around sources (concretely, pulsars) is not compatible with the effective average diffusion that our models predict for the Galaxy. This directly impacts Galaxy formation, our knowledge of the propagation process throughout the Galaxy and our...
The diffuse astrophysical neutrino flux was first detected by IceCube in
2013. With the high-probability association of a high-energy neutrino to the
blazar TXS0506+056 in 2017 and several more neutrino-blazar associations
since then, there is an indication that at least a non-negligible part of this
diffuse neutrino flux originates from blazars.
As over ninety stellar mass binary black...
LS 5039 is a high mass X-ray binary with an orbital periodicity of 3.9 days located about 1.5 degrees from the galactic plane. Previously, the H.E.S.S. telescope detected very high energy gamma-ray emissions from this source and measured the spectral energy in a broad inferior conjunction phase (0.45<phi<0.9) and a complimentary superior conjunction phase. However, the behavior of the...
The Compton Spectrometer and Imager (COSI) is a Small Explorer (SMEX) satellite mission selected by NASA for development. COSI is a wide-field telescope designed to survey the entire gamma-ray sky at 0.2-5 MeV. It provides imaging, spectroscopy, and polarimetry of astrophysical sources, and its germanium detectors provide excellent energy resolution for emission line studies. The science...
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...
Axions produced in the early universe can form bound clumps of Bose Einstein condensates, which are in some cases well described by a classical field with a single dominant angular frequency, close to the axion mass. In the vicinity of external electromagnetic fields, these axion clumps will start to radiate energy due to the axion-photon coupling. We will here consider the electromagnetic...
In this talk, we present model-independent constraints on dark matter and cosmic neutrinos through gravitational interactions on asteroidal objects. The bounds only rely on the matter density around the trajectories of the asteroids. The new bounds are model-independent but are most meaningful in constraining dark matter and cosmic neutrino scenarios with significant clustering.
We also...
We present the current status of the Radar Echo Telescope, an instrument to detect neutrinos of the highest energies. First, we present the status of the Radar Echo Telescope for Cosmic Rays (RET-CR), a prototype instrument that seeks to test the radar echo method in nature, using the in-ice cascade produced by the core of a cosmic-ray air shower as it impacts the ice. We present the current...
The high flux of hadronic cosmic rays and the detection of bright gamma-ray sources suggest a tight connection between them, which implies that Galactic neutrino sources must exist. However, none have been detected. Where are they? We outline constraints on the properties of hadronic PeVatrons based on the existing data. We introduce a new population-based approach, calibrated to the observed...
Dark matter candidates can arise from a wide range of extensions to the Standard Model. Simplified models with a small number of new particles allow for the optimisation and interpretation of dark matter and collider experiments, without the need for a UV-complete theory. In this talk, I will discuss the results from a recent GAMBIT study of global constraints on vector-mediated simplified...
The GAPS experiment is designed to conduct a dark matter search by measuring low-energy cosmic-ray antinuclei (antiprotons, antideuterons, antihelium) with a novel detection approach. For the case of antiprotons, a high-statistics measurement in the unexplored low-energy range will be conducted. In contrast, not a single cosmic antideuteron has been detected by any experiment thus far....
Confining hidden sectors at the GeV scale are well motivated by asymmetric
dark matter and naturalness considerations and can also give interesting collider signatures. Here we study such sectors connected to the Standard Model by a TeV scale mediator charged under both QCD and the dark force. Such a mediator admits a Yukawa
coupling between quarks and dark quarks which is generically...
Light dark sectors can explain the existence of dark matter and, if the new fermions carry lepton number, may also generate light neutrino masses. We revisit models where the dark photon $A^\prime$ couples to multiple generations of dark fermions. The decays $A^\prime$ are semi-visible: they contain visible particles but come accompanied by missing energy. We will show that these models can...
Precision results on cosmic-ray electrons are presented in the energy range from 0.5 GeV to 2.0 TeV based on 50 million electrons collected by the Alpha Magnetic Spectrometer on the International Space Station. In the entire energy range the electron and positron spectra have distinctly different magnitudes and energy dependences. At medium energies, the electron flux exhibits a significant...
High-energy collisions at the High-Luminosity Large Hadron Collider (HL-LHC) will pro- duce an enormous flux of particles along the beam collision axis that is not accessible by existing LHC experiments. Multi-particle production in the far-forward region is of par- ticular interest for astroparticle physics. High-energy cosmic rays produce large particle cascades in the atmosphere, extensive...
Galaxy mergers are a standard aspect of galaxy formation and evolution, and most (likely all) large galaxies contain supermassive black holes. As part of the merging process, the supermassive black holes should in-spiral together and eventually merge, generating a background of gravitational radiation in the nanohertz to microhertz regime. An array of precisely timed pulsars spread across the...
