Related papers: Probing Gamma-Ray Burst afterglows with the Cheren…
Very-high-energy gamma rays produce electron positron pairs in interactions with low-energy photons of extragalactic background light during propagation through the intergalactic medium. The electron-positron pairs generate secondary gamma…
Gamma-ray bursts (GRBs) are the most luminous astrophysical transients, known to be associated with core collapse of massive stars or mergers of two compact objects such as two neutron stars. They are followed by multi-wavelength afterglow…
Gamma-ray burst (GRB), GRB 221009A, a long-duration GRB, was observed simultaneously by the Water Cherenkov Detector Array (WCDA) and the Kilometer Squared Array (KM2A) of the Large High Altitude Air Shower Observatory (LHAASO) during the…
Recent observational efforts using imaging atmospheric Cherenkov telescopes (IACTs) have led to firm detections of very-high-energy (VHE) signals from bright gamma-ray bursts (GRBs), often at moderate redshifts. This work presents 15 years…
Gamma-ray bursts (GRBs) are some of the most extreme events in the Universe. As well as providing a natural laboratory for investigating fundamental physical processes, they might trace the cosmic star formation rate up to extreme redshifts…
The TESS exoplanet-hunting mission detected the rising and decaying optical afterglow of GRB 191016A, a long Gamma-Ray Burst (GRB) detected by Swift-BAT but without prompt XRT or UVOT follow-up due to proximity to the moon. The afterglow…
The upcoming Cherenkov Telescope Array (CTA) project is expected to provide unprecedented sensitivity in the low-energy ( <~100 GeV) range for Cherenkov telescopes. In order to exploit fully the potential of the telescopes the standard…
The Cherenkov Telescope Array (CTA) is the next generation facility of Imaging Atmospheric Cherenkov Telescopes. It will reach unprecedented sensitivity and energy resolution in very-high-energy gamma-ray astronomy. CTA will detect…
Indications of a GeV component in the emission from GRBs are known since the EGRET observations during the 1990's and they have been confirmed by the data of the Fermi satellite. These results have, however, shown that our understanding of…
For the proposed Cherenkov Telescope Array (CTA), a post-calibration point-source location accuracy of 3 seconds of arc is aimed for under favorable observing conditions and for gamma-ray energies exceeding 100 GeV. In this contribution,…
Gamma-ray emitting narrow-line Seyfert 1 ($\gamma$-NLS1) galaxies possibly harbour relatively low-mass black holes (10$^6$-10$^8$ M$_{\odot}$) accreting close to the Eddington limit, and share many characteristics with their sibling…
Long GRB 190114C, identified on January 14th, 2019, was the first Gamma-ray Burst that substantially violated the defined 10 GeV energy limit of the Synchrotron model, with an observed emission between 0.2 - 1 TeV and a low redshift of z =…
One of the major scientific objectives of the future Cherenkov Telescope Array (CTA) Observatory is the search for PeVatrons. PeVatrons are cosmic-ray factories able to accelerate nuclei at least up to the knee feature seen in the spectrum…
The successful launch and operation of NASA's Swift Gamma-Ray Burst Explorer open a new era for the multi-wavelength study of the very early afterglow phase of gamma-ray bursts (GRBs). GRB early afterglow information is essential to explore…
Short gamma-ray burst (SGRB) GRB 170817A was found to be related to a binary neutron star (BNS) merger. It is uncertain whether all SGRBs are caused by BNS mergers, and also under what conditions a BNS merger can cause a SGRB. As BNS…
Very high-energy gamma-ray measurements of distant blazars can be well explained by secondary gamma rays emitted by cascades induced by ultra-high-energy cosmic rays. The secondary gamma rays will enable one to detect a large number of…
Gamma-ray bursts (GRBs) comprise of short, bright, energetic flashes of emission from extragalactic sources followed by a longer afterglow phase of decreased brightness. Recent discoveries of very-high-energy (VHE, $\gtrsim 100$ GeV)…
The Cherenkov Telescope Array (CTA) is a future ground-based gamma-ray observatory that will provide unprecedented sensitivity and angular resolution for the detection of gamma rays with energies above a few tens of GeV. In comparison to…
Gamma-ray bursts (GRBs) are fascinating extragalactic objects. They represent a fantastic opportunity to investigate unique properties not exhibited in other sources. Multi-wavelength afterglow observations from some short- and…
Once completed, the Cherenkov Telescope Array (CTA) will be able to map the gamma-ray sky in a wide energy range from several tens of GeV to some hundreds of TeV and will be more sensitive than previous experiments by an order of magnitude.…