The LHC at CERN will undergo significant upgrades to enhance the collision rate in the High Luminosity LHC (HL-LHC), necessitating improvement of the ATLAS detector regarding higher resolution and efficiency. The Inner Detector will be replaced by the Inner Tracker. The transmission of the data signal will be handled by the Optosystem, managing the data and responsible for the opto-electrical...
The High Luminosity LHC will commence operation in 2029. A projected pileup of around 200 will result in consequences for data analysis complexity and radiation environment severity. The latter necessitates the replacement of the ATLAS Inner Detector with the all-silicon Inner Tracker (ITk). The Optosystem is a crucial part of the ITk readout system, performing data serialization, equalization...
Following Run III of the LHC, the ATLAS Inner Detector will undergo a series of upgrades to cope with the high radiation environment of the High Luminosity LHC. The Optosystem is the opto-electrical conversion system dedicated to the readout of the ATLAS Inner Tracker (ITk) Pixel detector that will replace the pixel detector of the Inner Detector. The testing of electrical characteristics of...
The Compact Muon Solenoid (CMS) experiment at CERN will undergo a major upgrade for the high-luminosity phase of the LHC (HL-LHC) starting in 2029. In addition to improving the detector rate capabilities and performance at higher luminosities, precision timing measurements are added to mitigate pile-up effects. We plan the extension of the timing capabilities to cover the full tracker...
While silicon photomultipliers (SiPMs) offer advantages over traditional photomultipliers, their adoption into space missions undergo challenges due to induced degradation by cosmic radiation. The University of Geneva, GSSI and FBK Research Foundation collaborate to define SiPMs for Terzina Cherenkov telescope by studying radiation hardness and light noise in situ. Using 50MeV proton-beam and...
In preparation of the operation of the CMS electromagnetic calorimeter (ECAL) barrel at the High Luminosity Large Hadron Collider (HL-LHC) the entire on-detector electronics will be replaced. The new readout electronic comprises 12240 very front end (VFE), 2448 front end (FE) and low voltage regulator (LVR) cards arranged into readout towers (RTs) of five VFE, one FE and one LVR cards. The...
As part of the Phase-2 upgrade of the Compact Muon Solenoid (CMS) experiment for the upcoming High Luminosity phase of LHC (HL-LHC), the Inner Tracker (IT) of CMS will be replaced with a new detector featuring increased rate capability, higher granularity, and improved radiation hardness. Furthermore the tracking coverage is extended up to $|\eta| \approx$ 4 by the Tracker Extended PiXel...
The MONOLITH H2020 ERC Advanced project aims at producing a high-granularity monolithic silicon pixel detector with picosecond-level time stamping. To obtain such extreme timing the project exploits: i) a fast and low-noise SiGe BiCMOS electronics; ii) a novel sensor concept, the Picosecond Avalanche Detector (PicoAD), that uses a patented multi-PN junction to engineer the electric field and...
The Mu3e experiment aims to detect charged lepton flavor violation through the decay chain μ+→e+e−e+. With sensitivities of 10^-15 in its initial phase and 10^-16 in the final phase, it improves upon prior experiments by four orders of magnitude. The innovative experimental concept is based on a tracking detector built from novel ultra-thin silicon pixel sensors and scintillating fibres and...
Mu3e is an experiment under construction at the Paul Scherrer Institute dedicated to the search for the charged lepton flavor violating muon decay, μ→eee, at branching fractions of 10^{-16}, extending the results from SINDRUM by four orders of magnitude.
To track low momentum particles while maintaining good vertex and timing resolution, a combined 4D tracking system integrating HV-MAPS,...
The current tracker detector of the LHCb experiment, based on Scintillating Fibres (SciFi) coupled to silicon photomultipliers (SiPMs), will be upgraded for the HL-LHC operations. The SiPMs will be exposed to a radiation environment, mainly dominated by fast neutrons, that will reach 3E12 neq/cm2 at the end of their lifetime. This will degrade their performance and compromise the overall...
LUX-ZEPLIN (LZ) is centered on a liquid xenon time projection chamber (LXe-TPC) searching for nuclear recoils induced by Weakly Interacting Massive Particles. One of the backgrounds for LZ are neutrons, as they result in nuclear recoils in the TPC. Surrounding the TPC is an Outer Detector which is used to veto neutron events in the TPC. The Outer Detector consists of 17t of gadolinium-loaded...
The LUX-ZEPLIN (LZ) experiment is a dual-phase liquid xenon time projection chamber aiming to make direct observation of weakly interacting massive particles (WIMPs). LZ published first results of data taken from December 2021 to May 2022, finding it consistent with background only, no WIMP hypothesis. Ensuring the accuracy of detector response with calibrations is vital. In the case of the...
Low-temperature covalent wafer-wafer bonding enables the creation of novel types of semiconductor particle detectors, including the monolithic integration of high-Z materials with conventional CMOS sensors. To investigate the influence of the bonding interface on the signal formation within such structures simple bonded pad diodes have been fabricated. We present results from two different...
The permanent neutron electric dipole moment (nEDM) is a very sensitive probe for exploring physics beyond the standard model at the low energy frontier, particularly regarding charge-parity (CP) violation. With the ultracold neutron (UCN) source at the Paul Scherrer Institut providing high neutron statistics and the new apparatus, the n2EDM experiment aims to measure the nEDM with a...
The n2EDM experiment at PSI aims to improve upon the best sensitivity measurements of the neutron electric dipole moment. This requires a stable and uniform magnetic field environment. To achieve this, a large system of coils surrounding the experimental area is implemented, called the Active Magnetic Shield (AMS). The AMS is engineered to counteract magnetic disturbances via a feedback loop...
The n2EDM experiment at the Paul Scherrer Institut (PSI) aims to improve the sensitivity of the measurement of the neutron electric dipole moment by a factor of ten. The neutron polarization must be conserved all along their path in the apparatus. To rotate the spin of the ultracold neutrons adiabatically with the magnetic field vector, spin transport coils (STC) are installed. We present the...
To increase the sensitivity of the neutron electric dipole moment (nEDM) by at least a factor of 10, next generation experiments will require corresponding improvements in statistics and systematics. The n2EDM experiment, currently being commissioned at the Paul Scherrer Institut, will employ an array of 112 optically pumped Cesium vapor magnetometers, measuring the magnetic field map with pT...
At PSI a high precision experiment is being set up to search for the muon electric dipole moment (muEDM) employing the frozen-spin technique. A muEDM larger than the Standard-Model prediction would be a sign for new physics. The search is conducted in two phases with a final precision of $6\cdot10^{-23}~$e$\cdot$cm. Eventually, this will improve the current best limit by three orders of...
The muEDM experiment at PSI aims to directly measure the electric dipole moment (EDM) of antimuons. In December 2023, a test beam was conducted to test the injection of muons at low magnetic fields for the muEDM experiment. The focus was to validate detector prototypes for use in the experiment and to assess changes in the momentum of the injected muons after altering the magnetic conditions,...
Muonic atom spectroscopy can be used to determine nuclear charge radii as muons orbit close to the nucleus, making them highly sensitive to nuclear properties. The muX experiment aims to determine the nuclear charge radius of Radium-226. However, radioactive isotopes are available only in microscopic quantities. To address this, the muX collaboration developed a novel technique based on...
In 2016 the ATOMKI collaboration measured an anomaly in the angular distribution of the pair produced by the M1 transition of the isoscalar 1+ state on 8Be, which might be explained by creation and decay of a boson, the X17, with mass 17.0 MeV/c2. The result was later confirmed in the 0-/0+ transition in Helium.
The apparatus of the MEG II experiment has been employed at the beginning of...
Spectroscopy of hadrons containing heavy-flavour quarks provides essential inputs to test models of quantum chromodynamics.
I will present some of the latest spectroscopy results from LHCb, covering both conventional and exotic hadrons.
Mirror-particles as hidden-sector copies of standard model particles could provide answers for several standing issues in particle physics. Mirror neutrons, for instance, could provide baryon number violation and be viable candidates for dark matter.
The mirror-neutron experiment at PSI was designed to search for anomalous disappearances of ultracold neutrons in the presence of varying...
Precision measurements of rare particle decays have gained significant interest as a way of indirectly searching for new physics. In these indirect searches, the properties of the rare decays are measured to a high precision in order to look for discrepancies between the experiment and the SM predictions that could be caused by new particles intervening with the decay. This contribution...
Accurate measurements of nuclear charge radii are essential for QED tests and benchmarking nuclear structure theory. Muonic atom spectroscopy is a particularly suited tool for measuring the RMS radii of nuclear charge distributions and has successfully provided data for very light and heavier nuclei. However, the energy range (~20-200 keV) for elements from lithium to neon remains poorly...
Flavor-changing neutral currents, forbidden at tree level in the Standard Model, serve as sensitive indicators of new physics. A particularly promising channel is the decay $B_s^0\rightarrow\mu^+\mu^-\gamma$, which is unaffected by chiral suppression, unlike its nonradiative counterpart. Leveraging recent studies at LHCb, we introduce a novel detection technique that employs photon conversion...
The development of radiative corrections and Monte Carlo tools for low-energy $e^+e^-$ experiments is relevant for high-precision tests of the Standard Model, such as the determination of the leading hadronic contribution to the muon $(g-2)$ or the electroweak precision fits.
Recently, there has been a renewed initiative to compare Monte Carlo tools. The main aim is to compare the available...
The decays B(s) -> KS KS proceed via flavor-changing neutral currents that are suppressed in the Standard Model and therefore provide greater sensitivity to new physics. And the latest measurements of their branching fractions exhibit some tension with the SM.
Since the time of the existing measurement, the LHCb experiment has collected a large amount of data and had several improvements to...
The dominance of matter over antimatter is one of the most puzzling questions in particle physics and cosmology. Since the Standard Model prohibits reactions violating the lepton number, the answer may lie in Beyond SM processes. The LEGEND experiment is designed to probe one such reaction: the neutrinoless double beta ($0\nu\beta\beta$) of $^{76}$Ge. Observing this decay would shed light on...
Rare Kaon meson decays serve as highly sensitive probes for both heavy and light New Physics. Notably, the $K_S\rightarrow\pi^+\pi^-\mu^+\mu^-$process, which is of order $10^{-14}$ in the Standard Model (SM), holds the potential to be enhanced by up to a factor of 100 in exotic Beyond the Standard Model (BSM) scenarios. The analysis of the $K_S\rightarrow\pi^+\pi^-\mu^+\mu^-$ decay is...
Theoretical studies have demonstrated that Semileptonic Hyperon Decays (SHD) can be sensitive to BSM dynamics that break lepton flavour universality (LFU). The LFU test observable, defined as the ratio between muon and electron modes, is sensitive to non standard contributions.
This talk will present the current status of the $\Lambda \to p \mu^- \bar{\nu}_\mu$ branching ratio measurement...
The decay process $B_{(c)}^+ \rightarrow \tau^+ \nu_{\tau}$ offers a direct experimental determination of the CKM element $V_{ub} (V_{cb})$, contributing to precision tests of the Standard Model. Additionally, the observation of this decay holds potential for probing extensions of the Standard Model, e.g. the two-Higgs doublet model and supersymmetry.
We aim to measure the $B_{(c)}^+...
Axion-like particles (ALPs) are hypothetical particles predicted in many extensions of the Standard Model (SM). ALPs can mediate the interactions between dark and ordinary matter, coupling to the different SM bosons. Thanks to its full software trigger and excellent vertex resolution, the LHCb experiment has excellent sensitivity for different ALPs, even at low masses, thus playing a unique...
The SHiP experiment is a pioneering initiative proposed at the CERN ECN3 to establish a general-purpose fixed target facility. Its primary objective is to explore the Hidden Sector portals domain and the potential discovery of novel particles envisaged in extensions of the Standard Model with unprecedented sensitivity. The central aim of the SHiP experiment is to unveil the existence of Feebly...
The application of state-of-the-art machine learning (ML) techniques based on graph or transformer architectures for LHC collision event reconstruction and classification will be presented. A focus is put on the application of ML methods to events which feature 2 top quarks and a large missing transverse momentum. Those events are especially interesting for searches beyond the standard model....
The ATLAS detector at the LHC records vast amounts of data. To ensure excellent detector performance, a number of checks are performed both during and after data-taking.
This study introduces a prototype algorithm designed to automatically identify detector anomalies in ATLAS liquid argon calorimeter data. The data is represented as a multi-channel time series, corresponding to average...
Pileup, or the presence of multiple independent proton-proton collisions within the same bunch-crossing, is critical to the production of enormous datasets at the LHC. However, the typical LHC physics analysis only considers a single collision in each bunch crossing; the pileup collisions are viewed as an annoyance to be rejected. By reconstructing these pileup collisions, it is possible to...
Pileup, or the presence of multiple independent proton-proton collisions within the same bunch-crossing, is critical to the production of enormous datasets at the LHC. However, the typical LHC physics analysis only considers a single collision in each bunch crossing; the pileup collisions are viewed as an annoyance to be rejected. By reconstructing these pileup collisions, it is possible to...
Pileup, or the presence of multiple independent proton-proton collisions within the same bunch-crossing, is critical to the production of enormous datasets at the LHC. However, the typical LHC physics analysis only considers a single collision in each bunch crossing; the pileup collisions are viewed as an annoyance to be rejected. By reconstructing these pileup collisions, it is possible to...
Short-distance (SD) effects in b→ s ll transitions can give large corrections to the SM prediction. They can however not be computed from first principles. In my talk I will present a neural network, that takes such SD effects into account, when inferring the Wilson coefficients C9 and C10 from b→ s ll angular observables. The model is based on likelihood-free inference and allows to put...
Experimental measurements of b-hadron decays encounter a broad spectrum of backgrounds due to the numerous possible decay channels with similar final states. Additionally, computational limitations necessitate simulating only the most significant backgrounds. Identifying the leading backgrounds requires a careful analysis of the final state particles, potential misidentifications and kinematic...
Imaging atmospheric Cherenkov telescopes (IACTs) observe extended air showers (EASs) initiated by the interaction of very-high-energy gamma rays and cosmic rays with the atmosphere. Besides the Cherenkov light emitted by the EAS, the IACT cameras continuously record light from the night sky background (NSB). The trigger and data acquisition system of IACT cameras is designed to reduce the NSB...
The Large-Sized Telescope (LST) is one of the three telescope types being built as part of the Cherenkov Telescope Array Observatory (CTAO). A next-generation camera that can be used in future LSTs is currently being developed. One of the main challenges is the 1GHz sampling rate baseline. After filtering events, the data rate must be reduced to around 30 kHz.
To achieve such a large...
The SND@LHC is a compact experiment that aims to observe and measure high flux of energetic neutrinos of all flavours from the LHC. Identifying neutrino interaction against the large background from neutral hadrons and muons is one of the main challenges. Current identification methods are based on reconstructing muon tracks and hit multiplicity, and only consider events that are in a fiducial...
FASER, an experiment at the LHC, aims to search for light, weakly interacting particles produced in proton-proton collisions at the ATLAS interaction point and travel in the far-forward direction. First search of detecting a light, long-lived particle decaying into photon pairs, using 2022 and 2023 collision data will be reported. Targeting axion-like particles (ALPs) primarily coupling to...
FASER, operating at the CERN-LHC throughout Run 3, has a dedicated high-energy neutrino physics programme using a 1.1-tonne tungsten target. The FASER$\nu$ detector, composed of interleaved emulsion films and tungsten plates, is designed for neutrino interaction measurements. Using a sub-sample of 2022 data, the first electron neutrinos at the LHC have been observed, and cross-sections in the...
In this talk I will present a new search for Beyond Standard Model (BSM) physics at the ATLAS experiment in an all-hadronic final state. The latter poses major challenges: the QCD interactions have the highest cross-sections at LHC, and are remarkably complex to simulate. Two analysis strategies were developed to deal with this difficult background, a cut-and-count analysis approach and a...
A search for direct top squark pair production is presented using ATLAS Run 2 and Run 3 data containing no leptons in the final state. The mass of this supersymmetric partner of the top quark is suggested to be at the TeV scale due to naturalness considerations and could therefore be produced at the LHC.
Different scenarios are considered where the top squark eigenstates decay into final...
Several LHC searches with multiple leptons in the final state point towards the existence of a new Higgs boson with a mass in the 140-160 GeV range, decaying mostly to a pair of W bosons. This dominant decay mode motivates a Higgs triplet with zero hypercharge, which also predicts a heavier-than-expected W-boson as indicated by the CDF-II measurement. Within this simple and predictive model,...
Many LHC measurements with multi-lepton final states and missing energy, in particular top differential distributions, show strong tensions with the SM predictions. I discuss how they can be explained by new physics within the ∆2HDMS and show the correlations to the hints for narrow resonances at the electroweak scale.
Based on: 2312.17314, 2308.07953.
The NA62 experiment, located at CERN SPS, is designed to study the ultra-rare decay K+ --> pi+ nu nubar. It has collected the world larges charged koan decay sample with a decay in flight technique. In this talk, the result with the data set collected in Run 1 (2016-2018) will be presented, which is the most accurate measurement achieved so far. Updates with Run 2 (2021 onwards) data set will...
The annihilation of dark-matter particles may lead to the production of monochromatic gamma rays. In this contribution, the search for spectral lines in the gamma-ray spectrum using eight years of data collected with the space-borne Dark Matter Particle Explorer (DAMPE) is presented. To improve the event selection, we developed two machine-learning algorithms that outperform all the standard...
The High-Energy cosmic-Radiation Detection facility (HERD) will be the largest calorimetric experiment for the direct detection of cosmic rays. HERD aims at probing dark-matter signatures in the electron and photon spectra up to 100 TeV. It will also measure the flux of cosmic protons and heavier nuclei up to a few PeV. HERD will be equipped with a scintillating-fiber tracker (FIT) for the...
Detecting UHECRs above 100 PeV involves observing the Cherenkov light that their induced extensive air showers (EAS) produce in crossing the Earth's limb.
Upping showers are caused by rare Earth-skimming neutrino-induced EAS, which are high-energy events of interest for multi-messenger astronomy.
The NUSES space mission, featuring Terzina and ZIRÈ payloads, serves as a precursor. In this...
The Large-Sized Telescope (LST) detects very high-energy gamma rays from 20 GeV to several TeV. The first prototype, LST-1, has been operational since November 2019 at La Palma's Roque de los Muchachos Observatory. Its calibration, essential for precision, utilizes the analysis of ring-shaped images from muons to determine optical throughput and point spread function. This involves...
Large-Sized Telescope target low-energy gamma rays, starting at 20 GeV. New silicon photomultiplier (SiPM) camera detect twice as much light as photomultiplier tube ones. This reduce detectable energy threshold, but separating signal from background remains a challenge. The SiPM-camera pixels are about 1/4 of the current camera allowing for higher-detail images which can be captured by AI...
In 1998, observations of distant stellar explosions provided evidence that the expansion of the Universe is accelerating. The cosmology community has struggled to find an explanation for this ever since, postulating the existence of a form of “dark energy” driving the expansion. However, the lack of theoretical understanding of its properties motivates the search for other explanations, most...
The XENONnT detector, hosted at the Laboratori Nazionali del Gran Sasso in Italy, is at the forefront of direct dark matter searches in the form of Weakly Interacting Massive Particles (WIMPs). Instrumented with an active target of 5.9 tonnes of liquid xenon (LXe), XENONnT employs a dual-phase time projection chamber designed to detect dark matter particles through its interactions with LXe...
Dual-phase time projection chambers (TPCs) provide the strongest constraints on the spin-independent WIMP-nucleon cross-section and great sensitivity towards other dark matter candidates. With greater exposure, this technology is expected to be able to probe dark matter cross-sections down to the neutrino fog, where coherent elastic neutrino-nucleus scattering processes pose an irreducible...
