A5100703645- Astrophysics and Cosmic Phenomena
- Gamma-ray bursts and supernovae
- Dark Matter and Cosmic Phenomena
- Astrophysical Phenomena and Observations
- Pulsars and Gravitational Waves Research
- Neutrino Physics Research
- Radio Astronomy Observations and Technology
- Particle Detector Development and Performance
- Particle physics theoretical and experimental studies
- Radiomics and Machine Learning in Medical Imaging
- Particle Accelerators and Free-Electron Lasers
- Nuclear Physics and Applications
- Astro and Planetary Science
- Cosmology and Gravitation Theories
- Geophysics and Gravity Measurements
- Galaxies: Formation, Evolution, Phenomena
- Radiation Detection and Scintillator Technologies
- Stellar, planetary, and galactic studies
- Ionosphere and magnetosphere dynamics
- Solar and Space Plasma Dynamics
- Astronomical Observations and Instrumentation
- Nuclear physics research studies
- Lightning and Electromagnetic Phenomena
- Reservoir Engineering and Simulation Methods
- Hydraulic Fracturing and Reservoir Analysis
University of the Witwatersrand
2015-2024
Parc Científic de la Universitat de València
2020-2024
Institute of Nuclear and Particle Physics
2021-2024
National Centre of Scientific Research "Demokritos"
2021-2024
Istituto Nazionale di Fisica Nucleare, Sezione di Napoli
2024
Taiwan Semiconductor Manufacturing Company (Taiwan)
2024
Neuroscience Institute
2024
Université Paris Cité
2021-2023
Centre National de la Recherche Scientifique
2021-2023
Centro de Investigaciones Energéticas, Medioambientales y Tecnológicas
2023
The third catalog of high-energy gamma-ray sources detected by the EGRET telescope on Compton Gamma Ray Observatory includes data from 1991 April 22 to 1995 October 3 (cycles 1, 2, 3, and 4 mission). In addition including more than second its supplement, this uses completely reprocessed (to correct a number mostly minimal errors problems). 271 (E > 100 MeV) in include single solar flare bright enough be as source, Large Magellanic Cloud, five pulsars, one probable radio galaxy detection (Cen...
This catalog summarizes 117 high-confidence ⩾0.1 GeV gamma-ray pulsar detections using three years of data acquired by the Large Area Telescope (LAT) on Fermi satellite. Half are neutron stars discovered LAT through periodicity searches in and radio around unassociated source positions. The pulsars evenly divided into groups: millisecond pulsars, young radio-loud radio-quiet pulsars. We characterize pulse profiles energy spectra derive luminosities when distance information exists. Spectral...
We present the first catalog of active galactic nuclei (AGNs) detected by Large Area Telescope (LAT), corresponding to 11 months data collected in scientific operation mode. The First LAT AGN Catalog (1LAC) includes 671 γ-ray sources located at high Galactic latitudes (|b|>10°) that are with a test statistic greater than 25 and associated statistically AGNs. Some multiple AGNs, consequently, 709 comprising 300 BL Lacertae objects, 296 flat-spectrum radio quasars, 41 AGNs other types, 72...
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...
<i>Context. <i/> AGILE is an Italian Space Agency mission dedicated to observing the gamma-ray Universe. The AGILE's very innovative instrumentation for first time combines a imager (sensitive in energy range 30 MeV–50 GeV), hard X-ray 18–60 keV), calorimeter 350 keV–100 MeV), and anticoincidence system. was successfully launched on 2007 April 23 from Indian base of Sriharikota inserted equatorial orbit with low particle background.<i>Aims. <i/>AGILE provides crucial data study active...
The first three months of sky-survey operation with the Fermi Gamma Ray Space Telescope (Fermi) Large Area (LAT) reveals 132 bright sources at |b|>10 deg test statistic greater than 100 (corresponding to about 10 sigma). Two methods, based on CGRaBS, CRATES and BZCat catalogs, indicate high-confidence associations 106 these known AGNs. This sample is referred as LAT Bright AGN Sample (LBAS). It contains two radio galaxies, namely Centaurus A NGC 1275, 104 blazars consisting 57 flat...
The well known Crab Nebula is at the center of SN1054 supernova remnant. It consists a rotationally-powered pulsar interacting with surrounding nebula through relativistic particle wind. emissions originating from and have been considered to be essentially stable. Here we report detection strong gamma-ray (100 MeV-10 GeV) flares observed by AGILE satellite in September, 2010 October, 2007. In both cases, unpulsed flux increased factor 3 compared non-flaring flux. flare luminosity short...
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...
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...
The next generation of water Cherenkov neutrino telescopes in the Mediterranean Sea are under construction offshore France (KM3NeT/ORCA) and Sicily (KM3NeT/ARCA). KM3NeT/ORCA detector features an energy detection threshold which allows to collect atmospheric neutrinos study flavour oscillation. This paper reports sensitivity this phenomenon. event reconstruction, selection classification described. determine mass ordering was evaluated found be 4.4 $\sigma$ if true is normal 2.3 inverted,...
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 detection by Astrorivelatore Gamma a Immagini Leggero (AGILE) satellite of terrestrial gamma ray flashes (TGFs) obtained with minicalorimeter (MCAL) detector operating in energy range 0.3–100 MeV. select events typically lasting few milliseconds spectral and directional selections consistent TGF characteristics previously reported other space missions. During period 1 June 2008 to 31 March 2009 we detect 34 high‐confidence showing millisecond durations geographical distribution...
We present the AGILE gamma-ray observations in energy range 50 MeV - 10 GeV of supernova remnant (SNR) W44, one most interesting systems for studying cosmic-ray production. W44 is an intermediate-age SNR (20, 000 years) and its ejecta expand a dense medium as shown by prominent radio shell, nearby molecular clouds, bright [SII] emitting regions. extend our analysis to energies substantially lower than previous measurements which could not conclusively establish nature radiation. find that...
Strong electric discharges associated with thunderstorms can produce terrestrial gamma-ray flashes (TGFs), i.e., intense bursts of x rays and $\ensuremath{\gamma}$ lasting a few milliseconds or less. We present in this Letter new TGF timing spectral data based on the observations Italian Space Agency AGILE satellite. determine that emission above 10 MeV has significant power-law component reaching energies up to 100 MeV. These results challenge theoretical models runaway electron...
The nine-year H.E.S.S. Galactic Plane Survey (HGPS) yielded the most uniform observation scan of inner Milky Way in TeV gamma-ray band to date. sky maps and source catalogue HGPS allow for a systematic study population pulsar wind nebulae found throughout last decade. To investigate nature evolution nebulae, first time we also present several upper limits regions around pulsars without detected nebula. Our data exhibit correlation surface brightness with spin-down power $\dot{E}$. This seems...
Analysis is presented for 15 months of data taken with the Large Area Telescope (LAT) on Fermi Gamma-ray Space 11 non-blazar active galactic nuclei (AGNs), including seven FRI radio galaxies and four FRII sources consisting two steep spectrum quasars. The broad line galaxy 3C 120 reported here as a γ-ray source first time. analysis based directional associations LAT in 3CR, 3CRR, MS4 (collectively referred to 3C-MS) catalogs. Seven eleven associated 3C-MS have spectral indices larger than...
Spectral lines are among the most powerful signatures for dark matter (DM) annihilation searches in very-high-energy $\gamma$-rays. The central region of Milky Way halo is one promising targets given its large amount DM and proximity to Earth. We report on a search monoenergetic spectral line from self-annihilations particles energy range 300 GeV 70 TeV using two-dimensional maximum likelihood method taking advantage both spatial features signal versus background. analysis makes use Galactic...
Supernova remnants exhibit shock fronts (shells) that can accelerate charged particles up to very high energies. In the past decade, measurements of a handful shell-type supernova in very-high-energy gamma rays have provided unique insights into acceleration process. Among those objects, RX$~$J1713.7-3946 (also known as G347.3-0.5) has largest surface brightness, allowing us perform most comprehensive study morphology and spatially resolved spectra any such gamma-ray source. Here we present...