« What is measured at the LHC, can be well explained by the Standard Model (SM) of Particle Physics. Nevertheless, several phenomena cannot be explained by the SM for example the matter-antimatter-asymmetry detected in our universe and no dark matter candidate was confirmed. In order to resolve these puzzles, it is important to identify good candidates for new physics (NP) searches. One of...
The Standard Model of particle physics states that the three charged leptons $e$, $\mu$ and $\tau$ have the same electroweak coupling (through $W^{\pm}$ and $Z^0$ bosons) and the only difference between them is their coupling to the Higgs field, i.e. their mass. Couple of independent experiments (BaBar, Belle and LHCb) have measured deviations from the SM prediction.
One of the anomalies...
One of the privileged ways to search for signs of New Physics (NP) beyond the Standard Model (SM), is the study of $b\rightarrow s\ell^{+}\ell^{-}$ ($\ell$= electron or muon) transitions which involve Flavour Changing Neutral Currents (FCNC) via box or loop diagrams. The LHCb experiment has recently published a set of measurements in tension with the SM predictions. The aim of this work is to...
Measurements of Higgs boson production cross-sections are carried out in the diphoton decay channel using 139 fb−1 of pp collision data at √s=13 TeV collected by the ATLAS experiment at the LHC. The analysis is based on the definition of 101 distinct signal regions using machine-learning techniques. The inclusive Higgs boson signal strength in the diphoton channel is measured to be...
The angle $\gamma$ of the Cabibbo-Kobayashi-Maskawa (CKM) Matrix had been until recent the least known parameters in the Standard Model of elementary particle physics and is still far from well known. The golden mode for measuring the angle $\gamma$ is a decay of $B^+\rightarrow DK^+$, where $D$ can be either $D^0$ or $\overline{D^0}$ and has a final state accesible from both of them so that...
For over a decade, deviations (“B anomalies”) from the standard model have been observed in $b$-hadron decays, for example, the departure from the lepton flavor universality in $b \to s\ell\ell$ and $b \to c\tau\nu$ transitions. Many new physics models trying to explain these results have larger couplings with the $\tau$-lepton, being 3rd generation, which predict an enhanced branching...
The JEM-EUSO collaboration develops a series of balloon and orbital telescopes to detect transient UV emission from the Earth atmosphere, with the primary goal to study ultrahigh-energy cosmic rays from space. These detectors are wide field-of-view telescopes with high temporal resolution (1-2.5 μs) and sensitivity provided by a large aperture. One of these detectors is currently operating...
Recent developments in heavy ions production increased access to alpha-emitting radioisotopes and opened the door to their use in internal radiotherapy[1]. Targeted alpha therapy is of interest for dedicated applications such as the treatment of disseminated brain metastases[2][3], their radiation range in biological matter covering only a few dozens of micrometers. However, when...
Actuellement, les radiothérapies les plus conventionnelles utilisées pour le traitement du cancer induisent des effets délétères dans le corps humain, et plus spécifiquement lorsque la tumeur cible est proche d’organes à risque.
L’utilisation de protons ou d’ions Carbonne (hadronthérapie) plutôt que des rayons X (thérapies plus conventionnelles), permet de délivrer une dose plus conforme à...
Searches for electric dipole moments (EDMs) of spin 1/2 particles such as the neutron are sensitive probes for CP
violation beyond the standard model, a key to solving the baryon asymmetry problem. In this presentation I give a
brief overview of n2EDM, an experiment aiming to measure the neutron EDM with a sensitivity of 1 × 10−27e.cm.
I then focus on two areas of my PhD work related to...
In-beam gamma-ray spectroscopy with high-velocity recoil nuclei requires very accurate Doppler correction. The Advanced GAmma Tracking Array (AGATA) is a new generation gamma-ray spectrometer that is capable of tracking gamma-rays with up to 5mm resolution which allows for accurate Doppler correction. AGATA is made of high-purity germanium crystals (about 50 available so far) assembled to form...
A non-monotonic net-proton kurtosis as a function of the collision
energy for very central collisions has been suggested and may be
confirmed by recent BES-II program results advocating the existence of
the QCD critical point. Fluctuations at the origin of this peculiar
behavior are produced in the highly dynamic environment of
ultra-relativistic collisions. Especially, the violent...
The High Acceptance Di-Electron Spectrometer (HADES) at GSI, Darmstadt,Germany is an experimental setup dedicated to study the hadronic matter in the region of large net baryon densities and moderate temperatures, using fixed-target heavy-ion collisions in the incident energy range of few GeV/nucleon. Dilepton emission is a favored probe for such studies as it gives undistorted information...
Symmetries play a crucial role in our current understanding of the fundamental properties of the Universe. Any combination of the three discrete operations, i.e. charge conjugation (C), parity (P), and time reversal (T) results in a CPT transformation. The corresponding CPT theorem states that CPT is an exact symmetry of nature and puts the following constraints on any quantum field theory...
Charged-particle pseudorapidity measurements help in understanding particle production mechanisms in high-energy hadronic collisions, from proton-proton to heavy-ion systems. Performing such measurements at forward rapidity, in particular, allows one to access the details of the phenomena associated with particle production in the fragmentation region. In ALICE, this measurement will be...
The presence of an unexpected significant excess of low $p_{T}$ $J/\psi$ over the expected hadronic $J/\psi$ production was confirmed in peripheral Pb$-$Pb collisions and observed for the first time in semi-central Pb$-$Pb collisions at $\sqrt{s_{NN}}$ = 5.02 TeV with ALICE at LHC. The measurements were performed in the dimuon decay channel at forward rapidity ($2.5 < y < 4$) and in the...
After the discovery of the Higgs boson in ATLAS and CMS collaborations, the standard model is complete. However, there are still remaining questions that the standard model cannot explain such as dark matter, etc. To understand these phenomena, we need to understand the property of this new particle and extend the standard model. Vector-like quark is one of the new candidates that will extend...
One of the most challenging problems of the Standard Model (SM) is the mass of the Higgs boson that diverges by taking the loop contributions into account. The decay of new particles like Vector-Like Quarks (VLQs) could be an interesting explanation as the final state in SM particles is well understood. We will present here the decay of a VLQ T' in a quark top and a Higgs boson in a dileptonic...
Mon projet de recherche est réalisé au sein de l’experience internationale CMS, qui analyse les collisions proton-proton de haute énergie produites par le LHC. Le projet est centré sur la recherche de particules lourdes, chargées et à long temps de vie (HSCP: Heavy Stable Charged Particles) prédites par certains modèles au delà du Modele Standard. Une premiere partie consiste à analyser les...
The Standard Model (SM) is unable to explain the predominance of matter over antimatter in our present universe. Matter and antimatter are linked by a CP-symmetry transformation, and current explanations involve a new source of CP symmetry breaking. An effective field theory (EFT) will be used to describe CP-symmetry violation, which will be searched for by analyzing the production and decay...
In the framework of the ATLAS Run-3 datataking period, an early-data analysis targeting emerging jets is in preparation. This analysis is the first effort to study this signature in the ATLAS collaboration.
Emerging jets are part of a global Beyond the Standard Model (BSM) theory called Dark QCD. This BSM theory predicts the existence of a new dark sector : containing QCD-like particles and...
In the context of a nuclear power reactor operation, decay heat is a thermal power
which continues to be generated after shut down. This is due to the radioactive decay of
fission products, minor actinides, and delayed fission of fissile nuclide. Hence, a proper
characterization of decay heat and is essential for reactor safety system design, spent
fuel transportation, and repository...
Understanding dense matter presents a big challenge at the actual time. On one hand QCD, the fundamental interaction of nuclear matter is known to be non-perturbative at such low energy regimes, and on the other hand relying on numerical approaches to solve QCD, also known as lattice QCD, is blocked by what is known as the "sign problem".
Thus effective nuclear modeling may be employed to...
The EDELWEISS collaboration performs light Dark Matter (DM) particle searches with high-purity germanium bolometers collecting both charge and phonon signals. Our recent results ([PhysRevD.106.062004][1]) using NbSi Transition Edge Sensor (TES) equipped detectors operated underground at the Laboratoire Souterrain de Modane (LSM) has shown the high relevance of this technology for future...
Almost a century ago, astrophysics observations lead to the suspicion of dark matter (DM) existence in gravitationally bound astrophysical objects such as our galaxy, the Milky Way. Since then, it became a pillar in modern cosmology. Yet, although many efforts were made to detect it, no DM signal have been observed in direct or indirect detection experiments.
There exists many candidates for...
L’expérience XENONnT est une expérience de détection directe de la matière noire utilisant une chambre à projection temporelle remplie de xénon liquide et gazeux. Elle a pour but principal de détecter la collision des WIMP avec les noyau de xénon. Les WIMP (Weakly Interacting Massive Particles) sont des particules théoriques candidates pour la matière noire. De part leur faible interaction...
Dark matter (DM) constitutes about 85% of the total matter content in the Universe and yet, we don’t know anything about its actual nature. In this talk, after an historical introduction, I will present my work on DM indirect detection, more especially the computation of X-ray constraints on sub-GeV (or “light”) DM. Photons from the galactic ambient bath see their energy boosted up to X-ray...
The discovery and confirmation of cosmic background radiation (CMB) is landmark evidence of the Big Bang model. Following the CMB fluctuation power spectrum measurements and other experiences, the LCDM model is established and considered the most successful cosmological model. The model of inflation, which is a period of accelerated expansion in the very early Universe, provides a mechanism...
Since the first direct evidence of gravitational waves in 2015 the LIGO and Virgo collaboration have provided important results for astrophysics, cosmology or fundamental physics. The upgrades of the detectors through the years has increased the sensitivity and the range of detection, challenging their calibration. This talk reports the latest updates for a calibration method based on the...
Since 2015, 90 gravitational waves (GW) signals, mainly produced by the merger of binary black hole (BBH), have been detected by the LIGO-Virgo-Kagra (LVK) collaboration. Beside being one of the most important discovery in physics of the 21st century, the detection of GWs is also the beginning of a new era, that opened a new window to study our universe. The LVK collaboration uses two...
The development of new facilities at CERN to study the properties of antimatter has revived the interest for the physics of interactions between matter and antimatter. These systems can constitute an efficient tool to determine the properties of antimatter but can also be used to improve our knowledge of matter, which is the main motivation for the antiproton Unstable Matter Annihilation...
Loosely bound nuclei are currently at the center of interest in low-energy nuclear physics. The deeper understanding of their properties provided by the shell model for open quantum systems changes the comprehension of many phenomena and offers new horizons for spectroscopic studies from the driplines to the well-bounded nuclei for states in the vicinity and above the first particle emission...
As neutrino oscillation physics enters the precision era, the modeling of neutrino-nucleus interactions constitutes an increasingly challenging source of systematic uncertainty for new measurements. To confront such uncertainties, a new generation of detectors is being developed, which aim to measure the complete (exclusive) final state of particles resulting from neutrino interactions. In...
The T2K experiment is a long baseline neutrino oscillation experiment located in Japan and dedicated to measuring the neutrino oscillations parameters. The muon neutrino beam produced at J-PARC is measured first by a group of near detectors, and then, after passing ~295 km, by a far water Cherenkov detector, where the appearance of electron neutrinos in a muon neutrino beam was observed for...
Prédite en 1974 par Daniel Z. Freedman et découverte en 2017 par l'expérience COHERENT, la diffusion cohérente élastique neutrino-noyau (souvent notée CENNS ou CEvNS en anglais) est un processus prometteur pour l'étude des neutrinos et de la physique au-delà du Modèle Standard à basse énergie. L'expérience RICOCHET, en cours de construction, est une des expériences qui vise à mesurer avec...
L'imagerie médicale nucléaire est une méthode qui consiste à suivre des médicaments radiomarqués utilisés pour créer des images dans le but de diagnostic, de suivi thérapeutique ou de recherche. La réduction de l'activité radio pharmaceutique appliquée au patient et le raccourcissement du temps d'exposition sont deux indicateurs cruciaux pour guider les améliorations de l'imagerie en médecine...
