Related papers: Extremely bright GRB 160625B with multi-episodes e…
We present the high-energy emission properties of GRB 160509A, from its prompt mission to late afterglow phase. GRB 160509A contains two emission episodes: 0-40s and 280-420s after the burst onset (t0). The relatively high fluence of GRB…
GRB 090618 offered an unprecedented opportunity to have coordinated data, by the best of the X and Gamma Ray observatories, of the nearest (z = 0.54) energetic source (10$^{54}$ erg). Using the Fermi-GBM observations of this GRB, we have…
We report on the detailed analysis of the high-energy extended emission from the short Gamma-Ray Burst (GRB) 081024B, detected by the Fermi Gamma-ray Space Telescope. Historically, this represents the first clear detection of temporal…
After more than 40 years from their discovery, the long-lasting tension between predictions and observations of GRBs prompt emission spectra starts to be solved. We found that the observed spectra can be produced by the synchrotron process,…
GRB 090926A was detected by both the GBM and LAT instruments on-board the Fermi Gamma-Ray Space Telescope. Swift follow-up observations began ~13 hours after the initial trigger. The optical afterglow was detected for nearly 23 days post…
We present the results of a detailed investigation of the prompt and afterglow emission in the HESS detected GRB 190829A. Swift and Fermi observations of the prompt phase of this GRB reveal two isolated sub-bursts or episodes, separated by…
The GeV emission of Gamma Ray Bursts, first detected by EGRET in an handful of bursts, is now an established property of roughly the 10% of all bursts, thanks to the Fermi/LAT observations. GRB 090510, a short burst, is particularly…
The composition of a jet is still an unsolved problem in gamma-ray bursts (GRBs). Several previous studies have suggested that the prompt emission spectrum of GRBs is likely to consist of a few components that may arise from different jet…
GRB 160709A is one of the few bright short gamma-ray bursts detected by both the Gamma-ray Burst Monitor and the Large Area Telescope on board the $Fermi$ $Gamma$-$ray$ $Space$ $Telescope$. The $\gamma$-ray prompt emission of GRB 160709A is…
The Lorentz factor of a relativistic jet and its evolution during the jet expansion are difficult to estimate, especially for the jets in gamma-ray bursts (GRBs). However, it is related to the understanding of jet physics. Owing to the…
The cosmic formation rate of long Gamma Ray Bursts (LGRBs) encodes the evolution, across cosmic times, of their progenitors' properties and of their environment. The LGRB formation rate and the luminosity function, with its redshift…
We present the detection of a blackbody component in GRB 160107A emission by using the combined spectral data of the CALET Gamma-ray Burst Monitor (CGBM) and the MAXI Gas Slit Camera (GSC). The MAXI/GSC detected the emission $\sim$45 s…
Millilensing of Gamma-Ray Bursts (GRBs) is expected to manifest as multiple emission episodes in a single triggered GRB with similar light-curve patterns and similar spectrum properties. Identifying such lensed GRBs could help improve…
Since the advent of the Swift satellite it has been possible to obtain precise localisations of GRB positions of sub-arcsec accuracy within seconds, facilitating ground-based robotic telescopes to automatically slew to the target within…
Early and late multiwavelength observations play an important role in determining the nature of the progenitor, circumburst medium, physical processes and emitting regions associated to the spectral and temporal features of bursts. GRB…
We present the discovery of the radio afterglow of the most distant ultra-long gamma-ray burst (GRB) detected to date, GRB~220627A at redshift $z=3.084$. Its prompt gamma-ray light curve shows a double-pulse profile, with the pulses…
Long $\rm \gamma$-ray bursts (GRBs) are produced by the dissipation of ultra-relativistic jets launched by newly-born black holes after the collapse of massive stars. Right after the luminous and highly variable $\gamma$-ray emission, the…
The high energy emission from Gamma-ray Bursts has some interesting features, including the absence of the GeV excess in the prompt spectrum, the delayed onset of the GeV emission, and the longer duration of the GeV emission than the prompt…
Starting from the Swift sample we define a complete sub-sample of 58 bright long Gamma Ray Bursts (GRB), 55 of them (95%) with a redshift determination, in order to characterize their properties. Our sample (BAT6) allows us to study the…
Launched on June 11, 2008, the LAT instrument onboard the $Fermi$ Gamma-ray Space Telescope has provided a rare opportunity to study high energy photon emission from gamma-ray bursts. Although the majority of such events (27) have been iden…