Related papers: Probing Gamma-Ray Burst afterglows with the Cheren…
Gamma-ray burst astronomy has undergone a revolution in the last three years, spurred by the discovery of fading long-wavelength counterparts. We now know that at least the long duration GRBs lie at cosmological distances with estimated…
It is usually thought that long-duration gamma-ray bursts (GRBs) are associated with massive star core collapse, whereas short-duration GRBs are associated with mergers of compact stellar binaries. The discovery of a kilonova associated…
The compact X-ray binary system Cyg X-3 has been recently discovered as a source of GeV gamma-rays by the AGILE and the {\it Fermi} satellites. It shows emission features in the GeV gamma-rays similar to other gamma-ray binaries which were…
The Cherenkov Telescope Array (CTA) is the next generation ground-based $\gamma$-ray observatory. It will provide an order of magnitude better sensitivity and an extended energy coverage, 20 GeV - 300 TeV, relative to current Imaging…
High energy gamma-ray astronomy is a newly emerging and very successful branch of astronomy and astrophysics. Exciting results have been obtained by the current generation Cherenkov telescope systems such as H.E.S.S., MAGIC, VERITAS and…
The role of the Rossi X-ray Timing Explorer (RXTE) in the study of Gamma-ray Bursts (GRBs) is reviewed. Through April 2001, the All-Sky Monitor (ASM) and the Proportional Counter Array (PCA) instruments have detected 30 GRBs. In 16 cases,…
We consider some general implications of bright gamma-ray counterparts to fast radio bursts (FRBs). We show that even if these manifest in only a fraction of FRBs, gamma-ray detections with current satellites (including Swift) can provide…
The binary systems that have been detected in gamma rays have proven very useful to study high-energy processes, in particular particle acceleration, emission and radiation reprocessing, and the dynamics of the underlying magnetized flows.…
Gamma-ray bursts (GRBs) are brief flashes of gamma rays, considered to be the most energetic explosive phenomena in the Universe. The emission from GRBs comprises a short (typically tens of seconds) and bright prompt emission, followed by a…
In many theoretical models of gamma-ray bursts (GRBs) and their afterglows, the emission of photons above 100 GeV is predicted. The Large Area Telescope (LAT) on-board the Fermi Gamma-ray Space Telescope has detected delayed, high-energy…
Particle acceleration in relativistic collisionless shocks remains an open problem in high-energy astrophysics. Particle-in-cell (PIC) simulations predict that electron acceleration in weakly magnetized shocks proceeds via small-angle…
If the efficiency for producing $\gamma$-rays is the same in short duration ($\siml 2$ s) Gamma-Ray Bursts (GRBs) as in long duration GRBs, then the average kinetic energy of short GRBs must be $\sim 20$ times less than that of long GRBs.…
The detection of very-high-energy gamma rays from supernova remnant shells testifies of the acceleration of particles at strong shocks. Many aspects of the particle acceleration remain however unclear. The study of individual objects is…
The recent detection of a very high energy (VHE) emission from Gamma-Ray Bursts (GRBs) above 100 GeV performed by the MAGIC and H.E.S.S. collaborations, has represented a significant, long-awaited result for the VHE astrophysics community.…
Among all the high-energy environments of our Galaxy, the Galactic Center (GC) region is definitely the richest. It harbors a large amount of non-thermal emitters, including the closest supermassive black hole, dense molecular clouds,…
We compute the sensitivity to dark matter annihilations for the forthcoming large Cherenkov Telescope Array (CTA) in several primary channels and over a range of dark matter masses from 30 GeV up to 80 TeV. For all channels, we include…
Ground-based gamma-ray astronomy has experienced a major breakthrough in the last decade thanks to the advent of new generation instruments such as H.E.S.S., MAGIC, Milagro and VERITAS. A large variety of cosmic particle accelerators has…
Observations from multiple gamma-ray telescopes have uncovered a high energy gamma-ray source spatially coincident with the Galactic center. Recently, a compelling model for the broad-band gamma-ray emission has been formulated which posits…
The Cherenkov Telescope Array (CTA) will be the next generation observatory employing different types of Cherenkov telescopes for the detection of particle showers initiated by very-high-energy gamma rays. A good knowledge of the Earth's…
Around 160 gamma-ray pulsars were discovered by the Fermi Large Area Telescope (LAT) since 2008. The most energetic of them, 12 objects with emission above 25 GeV, are suitable candidates for the detection with the current and future…