C. Boisson
A5046697499- Astrophysics and Cosmic Phenomena
- Gamma-ray bursts and supernovae
- Astrophysical Phenomena and Observations
- Dark Matter and Cosmic Phenomena
- Radio Astronomy Observations and Technology
- Astronomy and Astrophysical Research
- Particle Detector Development and Performance
- Neutrino Physics Research
- Pulsars and Gravitational Waves Research
- Stellar, planetary, and galactic studies
- Astronomical Observations and Instrumentation
- Galaxies: Formation, Evolution, Phenomena
- Particle Accelerators and Free-Electron Lasers
- Cosmology and Gravitation Theories
- Particle physics theoretical and experimental studies
- Scientific Computing and Data Management
- Astrophysics and Star Formation Studies
- Distributed and Parallel Computing Systems
- Prenatal Screening and Diagnostics
- Environmental Monitoring and Data Management
- Advanced Computational Techniques and Applications
- Research Data Management Practices
- Pregnancy and preeclampsia studies
- Solar and Space Plasma Dynamics
- Folate and B Vitamins Research
Université Paris Sciences et Lettres
2015-2024
Centre National de la Recherche Scientifique
2015-2024
Laboratoire Univers et Théories
2015-2024
Université Paris Cité
2015-2024
Janssen (France)
2012-2024
Galaxies, Etoiles, Physique et Instrumentation
2016-2024
TU Dortmund University
2019-2023
Durham University
2005-2023
Observatoire de Paris
2002-2023
University of Łódź
2023
Ground-based gamma-ray astronomy has had a major breakthrough with the impressive results obtained using systems of imaging atmospheric Cherenkov telescopes. huge potential in astrophysics, particle physics and cosmology. CTA is an international initiative to build next generation instrument, factor 5-10 improvement sensitivity 100 GeV 10 TeV range extension energies well below above TeV. will consist two arrays (one north, one south) for full sky coverage be operated as open observatory....
The high-frequency peaked BL Lac PKS 2155-304 at redshift z = 0.116 is a well-known VHE (>100 GeV) γ-ray emitter. Since 2002 its flux has been monitored using the H.E.S.S. stereoscopic array of imaging atmospheric Cerenkov telescopes in Namibia. During 2006 July dark period, average was measured to be more than 10 times typical values observed from object. This article focuses solely on an extreme outburst detected early hours 28 (MJD 53,944). during this I(>200 (1.72 ± 0.05stat 0.34syst) ×...
The Cherenkov Telescope Array, CTA, will be the major global observatory for very high energy gamma-ray astronomy over next decade and beyond. scientific potential of CTA is extremely broad: from understanding role relativistic cosmic particles to search dark matter. an explorer extreme universe, probing environments immediate neighbourhood black holes voids on largest scales. Covering a huge range in photon 20 GeV 300 TeV, improve all aspects performance with respect current instruments....
The very large collection area of ground-based gamma-ray telescopes gives them a substantial advantage over balloon or satellite based instruments in the detection very-high-energy (>600 GeV) cosmic-ray electrons. Here we present electron spectrum derived from data taken with High Energy Stereoscopic System (H.E.S.S.) imaging atmospheric Cherenkov telescopes. In this measurement, first type, are able to extend measurement beyond range accessible direct measurements. We find evidence for...
We report on a survey of the inner part Galactic Plane in very high energy gamma-rays, with H.E.S.S. Cherenkov telescope system. The between +-30deg longitude and +-3deg latitude relative to Centre was observed 500 pointings for total 230 hours, reaching an average flux sensitivity 2% Crab Nebula at energies above 200 GeV. Fourteen previously unknown sources were detected significance level greater than 4 sigma after accounting all trials involved search. Initial results eight most...
The measurement of an excess in the cosmic-ray electron spectrum between 300 and 800 GeV by ATIC experiment has - together with PAMELA detection a rise positron fraction up to 100 motivated many interpretations terms dark matter scenarios; alternative explanations assume nearby source like pulsar or supernova remnant. Here we present H.E.S.S. starting at 340 GeV. While overall flux measured is consistent data within statistical systematic errors, exclude pronounced peak as suggested for...
We report the detection of a point-like source very high energy (VHE) gamma-rays coincident within 1' Sgr A*, obtained with H.E.S.S. array Cherenkov telescopes. The exhibit power-law spectrum spectral index -2.2 +/- 0.09 0.15 and flux above 165 GeV threshold (1.82 0.22) * 10^-7 m^-2 s^-1. measured differ substantially from recent results reported in particular by CANGAROO collaboration.
We present the results of most comprehensive survey Galactic plane in very high-energy (VHE) gamma-rays, including a public release sky maps, catalog VHE sources, and discovery 16 new sources gamma-rays. The High Energy Spectroscopic System (H.E.S.S.) (HGPS) was decade-long observation program carried out by H.E.S.S. I array Cherenkov telescopes Namibia from 2004 to 2013. observations amount nearly 2700 h data, covering at longitudes l = 250 deg 65 latitudes |b| < 3 deg. In addition...
The inner region of the Milky Way halo harbors a large amount dark matter (DM). Given its proximity, it is one most promising targets to look for DM. We report on search annihilations DM particles using γ-ray observations towards 300 pc Way, with H.E.S.S. array ground-based Cherenkov telescopes. analysis based 2D maximum likelihood method Galactic Center (GC) data accumulated by over last 10 years (2004-2014), and does not show any significant signal above background. Assuming Einasto...
A search for a very-high-energy (VHE; ≥100 GeV) γ-ray signal from self-annihilating particle dark matter (DM) is performed towards region of projected distance r∼45-150 pc the Galactic center. The background-subtracted spectrum measured with High Energy Stereoscopic System (H.E.S.S.) instrument in energy range between 300 GeV and 30 TeV shows no hint residual flux. Assuming conventional Navarro-Frenk-White Einasto density profiles, limits are derived on velocity-weighted annihilation cross...
Gamma-ray line signatures can be expected in the very-high-energy (${E}_{\ensuremath{\gamma}}>100\text{ }\text{ }\mathrm{GeV}$) domain due to self-annihilation or decay of dark matter (DM) particles space. Such a signal would readily distinguishable from astrophysical $\ensuremath{\gamma}$-ray sources that most cases produce continuous spectra span over several orders magnitude energy. Using data collected with H.E.S.S. instrument, upper limits on linelike emission are obtained energy range...
Current Cherenkov telescopes have identified a population of ultra-high-frequency peaked BL Lac objects (UHBLs), also known as extreme blazars, that exhibit exceptionally hard TeV spectra, including 1ES 0229+200, 0347-121, RGB J0710+591, 1101-232, and 1218+304. Although one-zone synchrotron-self-Compton (SSC) models been generally successful in interpreting the high-energy emission observed other objects, they are problematic for UHBLs, necessitating very large Doppler factors and/or...
Gamma-ray bursts (GRBs), which are bright flashes of gamma rays from extragalactic sources followed by fading afterglow emission, associated with stellar core collapse events. We report the detection very-high-energy (VHE) GRB 190829A, between 4 and 56 hours after trigger, using High Energy Stereoscopic System (H.E.S.S.). The low luminosity redshift 190829A reduce both internal external absorption, allowing determination its intrinsic energy spectrum. Between energies 0.18 3.3 tera-electron...
We provide an updated assessment of the power Cherenkov Telescope Array (CTA) to search for thermally produced dark matter at TeV scale, via associated gamma-ray signal from pair-annihilating particles in region around Galactic centre. find that CTA will open a new window discovery potential, significantly extending range robustly testable models given standard cuspy profile density distribution. Importantly, even cored profile, projected sensitivity be sufficient probe various...
SS 433 is a microquasar, stellar binary system that launches collimated relativistic jets. We observed in gamma rays using the High Energy Stereoscopic System (H.E.S.S.) and found an energy-dependent shift apparent position of gamma-ray emission from parsec-scale These observations trace energetic electron population indicate inverse Compton scattering mechanism rays. Our modeling morphology constrains location particle acceleration requires abrupt deceleration jet flow. infer presence...
We report the discovery of very-high-energy (VHE) γ-ray emission binary system PSR B1259-63/SS 2883 a radio pulsar orbiting massive, luminous Be star in highly eccentric orbit.The observations around 2004 periastron passage were performed with four 13 m Cherenkov telescopes HESS experiment, recently installed Namibia and full operation since December 2003.Between February June 2004, signal from was detected total significance above 13σ.The flux found to vary significantly on timescales days...
X-ray binaries are composed of a normal star in orbit around neutron or stellar-mass black hole. Radio and x-ray observations have led to the presumption that some called microquasars behave as scaled-down active galactic nuclei. Microquasars resolved radio emission is thought arise from relativistic outflow akin nuclei jets, which particles can be accelerated large energies. Very high energy gamma-rays produced by interactions these been observed several Using High Energy Stereoscopic...
The detection of fast variations the tera-electron volt (TeV) (10(12) eV) gamma-ray flux, on time scales days, from nearby radio galaxy M87 is reported. These are about 10 times as those observed in any other wave band and imply a very compact emission region with dimension similar to Schwarzschild radius central black hole. We thus can exclude several sites processes production. observations confirm that TeV gamma rays emitted by extragalactic sources than blazars, where jets not...
We present deep H.E.S.S. observations of the supernova remnant (SNR) RX J1713.7-3946. Combining data three years - from 2003 to 2005 we obtain significantly increased statistics and energy coverage as compared earlier & 2004 results. The are analysed separately for different years. Very good agreement gamma-ray morphology differential spectra is found when comparing combined image reveals J1713.7-3946 with unprecedented precision. An angular resolution 0.06 deg achieved, revealing...
We present results from deep observations of the Galactic shell-type supernova remnant (SNR) RX J1713.7-3946 (also known as G347.3-0.5) conducted with complete H.E.S.S. array in 2004. Detailed morphological and spatially resolved spectral studies reveal very-high-energy (VHE -- Energies E > 100 GeV) gamma-ray aspects this object unprecedented precision. Since is first in-depth analysis an extended VHE source, we a thorough discussion our methodology investigations possible sources...
Very high energy gamma-rays probe the long-standing mystery of origin cosmic rays. Produced in interactions accelerated particles astrophysical objects, they can be used to image particle accelerators. A first sensitive survey inner part Milky Way with High Energy Stereoscopic System (H.E.S.S.) reveals a population eight previously unknown firmly detected sources very gamma-rays. At least two have no known radio or X-ray counterpart and may representative new class `dark' nucleonic ray sources.