A5021922176- Dark Matter and Cosmic Phenomena
- Astrophysics and Cosmic Phenomena
- Gamma-ray bursts and supernovae
- Particle physics theoretical and experimental studies
- Neutrino Physics Research
- Pulsars and Gravitational Waves Research
- Radio Astronomy Observations and Technology
- Galaxies: Formation, Evolution, Phenomena
- Particle Detector Development and Performance
- Atomic and Subatomic Physics Research
- Cosmology and Gravitation Theories
- Astrophysical Phenomena and Observations
- Scientific Research and Discoveries
- Computational Physics and Python Applications
- Stellar, planetary, and galactic studies
- Astronomy and Astrophysical Research
- Distributed and Parallel Computing Systems
- Quantum Chromodynamics and Particle Interactions
- Black Holes and Theoretical Physics
- Geophysics and Gravity Measurements
- Photocathodes and Microchannel Plates
- CCD and CMOS Imaging Sensors
- Radiation Detection and Scintillator Technologies
- Soil Moisture and Remote Sensing
- Radioactive Decay and Measurement Techniques
Laboratoire d'Annecy-le-Vieux de Physique Théorique
2021-2025
Centre National de la Recherche Scientifique
2021-2024
Laboratoire d’Annecy de Physique des Particules
2023-2024
University of Nova Gorica
2017-2024
TU Dortmund University
2023
University of Łódź
2023
Centro de Investigaciones Energéticas, Medioambientales y Tecnológicas
2023
University of Turku
2023
Niels Brock
2023
University of Copenhagen
2023
The grand challenges of contemporary fundamental physics---dark matter, dark energy, vacuum inflation and early universe cosmology, singularities the hierarchy problem---all involve gravity as a key component. And all gravitational phenomena, black holes stand out in their elegant simplicity, while harbouring some most remarkable predictions General Relativity: event horizons, ergoregions. hitherto invisible landscape Universe is being unveiled before our eyes: historical direct detection...
We investigate the characteristics of gamma-ray signal following decay MeV-scale Axion-Like Particles (ALPs) coupled to photons which are produced in a Supernova (SN) explosion. This analysis is first include production heavier ALPs through photon coalescence process, enlarging mass range that could be observed this way and giving stronger bound from observation SN 1987A. Furthermore, we present new analytical method for calculating predicted ALP decays. With can rigorously prove validity an...
The Fermi-LAT observations of SN 2023ixf, a type II supernova in the nearby Pinwheel Galaxy, Messier 101 (M101), presents us with an excellent opportunity to constrain MeV-scale axionlike particles (ALPs). By examining photon decay signature from heavy ALPs that could be produced explosion, existing constraints on ALP-photon coupling can improved, under optimistic assumptions, by up factor <a:math xmlns:a="http://www.w3.org/1998/Math/MathML"...
The gamma-ray Fermi-LAT Galactic centre excess (GCE) has puzzled scientists for over 15 years. Despite ongoing debates about its properties, and especially spatial distribution, nature remains elusive. We scrutinize how the estimated morphology of this depends on models diffuse emission, focusing particularly extent to which plane point sources are masked. Our main aim is compare a spherically symmetric - potentially arising from annihilation dark matter (DM) particles with boxy expected if...
Axion-like particles (ALPs) may be abundantly produced in core-collapse (CC) supernovae (SNe), hence the cumulative signal from all past SN events can create a diffuse flux peaked at energies of about 25~MeV. We improve upon modeling ALPs by including set CC models with different progenitor masses, as well effects failed SNe -- which yield formation black holes instead explosions. Relying on coupling strength to photons and related Primakoff process, ALP is converted into gamma rays while...
A future Galactic Supernova (SN) explosion can lead to a gamma-ray signal induced by ultralight Axion-Like Particles (ALPs) thermally produced in the SN core and converted into high-energy photons magnetic field. The detection of such is reach Large Area Telescope aboard \emph{Fermi} Gamma-Ray Space Telescope. observation emission from has sensitivity $g_{a\gamma}\gtrsim 4\times 10^{-13}$ GeV$^{-1}$ for at fiducial distance $10$ kpc would allow us reconstruct ALP-photon coupling within...
Numerous observations confirm the existence of dark matter (DM) at astrophysical and cosmological scales. Theory simulations galaxy formation predict that DM should cluster on small scales in bound structures called sub-halos or clumps. While most massive host baryonic matter, less massive, unpopulated could be abundant Milky Way (MW), as well yield high-energy gamma rays final products annihilation. Recently, it has been highlighted brightest halos also have a sizeable extension sky. In...
The Andromeda (M31) and Triangulum (M33) galaxies are the closest Local Group to Milky Way, being only 785 870 kpc away. These two provide an independent view of high-energy processes that often obscured in our own Galaxy, including possible signals dark matter (DM) particle interactions. Fermi Large Area Telescope (Fermi-LAT) preliminary eight year list sources includes both M31, which is detected as extended with a size about 0.4$^\circ$, M33, point-like source. spatial morphology M31...
ABSTRACT A deep survey of the Large Magellanic Cloud at ∼0.1–100 TeV photon energies with Cherenkov Telescope Array is planned. We assess detection prospects based on a model for emission galaxy, comprising four known emitters, mock populations sources, and interstellar galactic scales. also detectability 30 Doradus SN 1987A, constraints that can be derived nature dark matter. The will allow fine spectral studies N 157B, 132D, LMC P3, C, half dozen other sources should revealed, mainly...
The authors model the latest sub-PeV Galactic diffuse emission from gamma-ray data to assess a hitherto unexplored region of parameter space for Axion-like Particles (ALPs). They constrain photon-ALP coupling constant ALP masses $\ensuremath{\le}2\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}7}$ eV, further closing mass gap limits Axion Dark Matter Experiment (ADMX).
Abstract 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 (MSPs). This study investigates how gamma-ray emission model ( γ EM) used center analyses affects interpretation of GCE's nature. To address this issue, we construct an ultra-fast and powerful inference pipeline based on convolutional Deep Ensemble Networks. We explore two...
At GeV energies, the sky is dominated by interstellar emission from Galaxy. With limited statistics and spatial resolution, accurately separating point sources therefore challenging. Here we present first application of deep learning based algorithms to automatically detect classify gamma-ray data. For concreteness refer this approach as AutoSourceID. To sources, utilized U-shaped convolutional networks for image segmentation {\it k}-means source clustering localization. We also explored...
Abstract Axion-like particles (ALPs) coupled to nucleons can be efficiently produced in the interior of protoneutron stars (PNS) during supernova (SN) explosions. If these ALPs are also photons they convert into gamma rays Galactic magnetic field. This SN-induced gamma-ray burst observable by telescopes like Fermi -LAT if SN is field view detector. We show that spectrum sensitive production processes core. In particular, nucleon-nucleon bremsstrahlung dominant axion channel, one expects a...
The Andromeda Galaxy (M31) is a nearby (∼780 kpc) galaxy similar to our own Milky Way. Observational evidence suggests that it resides in large halo of dark matter (DM), making good target for DM searches. We present search gamma rays from M31 using 1017 days data the High Altitude Water Cherenkov (HAWC) Observatory. With its wide field view and constant monitoring, HAWC well-suited extended targets like M31. No annihilation or decay signal was detected masses 1 100 TeV b, t, τ+τ−, μ+μ−,...
A new measurement of a spatially extended gamma-ray signal from the center Andromeda galaxy (M31) has been recently published by Fermi-LAT collaboration, reporting that emission broadly resembles so-called Galactic excess (GCE) Milky Way (MW). At same time, evidence is accumulating on millisecond pulsar (MSPs) origin for GCE. These elements prompt us to compare mentioned observations with what is, perhaps, simplest model an MSP population, solely obtained rescaling luminosity function...
Abstract Millisecond pulsars (MSPs) are abundant in globular clusters (GCs), which offer favorable environments for their creation. While the advent of recent, powerful facilities led to a rapid increase MSP discoveries GCs through pulsation searches, detection biases persist. In this work, we investigate ability current and future detections constrain parameters population careful study luminosity function. Parameters interest number MSPs hosted by GC, as well mean width function, typically...
ABSTRACT The recently identified source class of pulsar haloes may be numerous and bright enough in the TeV energy range to constitute a large fraction sources that will observed with Cherenkov Telescope Array (CTA). In this work, we quantify prospects for detecting characterizing observations projected Galactic Plane Survey (GPS), using simple phenomenological diffusion model individual their population Milky Way. Our ability uncover constrain main physical parameters CTA GPS is assessed...
Astrophysical observations currently provide the only robust, empirical measurements of dark matter. In coming decade, astrophysical will guide other experimental efforts, while simultaneously probing unique regions matter parameter space. This white paper summarizes that can constrain fundamental physics in era LSST. We describe how inform our understanding properties matter, such as particle mass, self-interaction strength, non-gravitational interactions with Standard Model, and compact...
Core-collapse supernovae (SNe) have been identified as a promising target to probe the existence of axion-like-particles (ALPs). The cumulative signal from all past SNe events would contain an ALP component and create diffuse flux peaked at energies $\mathcal{O}(50)$ MeV. Due their coupling photons related Primakoff process, is converted into gamma-ray while traversing magnetic field Milky Way. spatial morphology this expected follow shape Galactic lines. We perform template-based analysis...
We present a numerical linear programming bootstrap to construct dual model scattering amplitudes. Dual models describe tree-level exchanges of higher spin resonances in theories like string theory and large $N$ gauge theories. Despite being very simple objects, their has proven challenging due slow convergence the infinite sums over resonances. Our succeeds thanks an efficient parametrization amplitude terms Mandelstam-Regge poles use combined regions that make crossing symmetry...