Short gamma-ray bursts (SGRBs) are located at cosmological distances and their progenitors are compact binary mergers. These luminous events last for $T_{90}<2$ seconds. However, they are not the only events that last for that long. Magnetars, which are located in our galaxy or in nearby galaxies produce giant flares (MGFs). MGFs are short-hard energetic gamma-ray transients, similar to SGRBs...
Gamma Ray Bursts (GRBs) are the most powerful explosions in the universe, emitting more energy in a few seconds than our sun will emit in its entire lifetime. As a result, these explosions are excellent laboratories for exploring the interplay between matter and radiation in extreme environments. This interplay is integral to understanding astrophysical jets and the various compact objects...
Radiation-mediated shocks (RMSs) below the photosphere may play an important role in the prompt emission of gamma-ray bursts (GRBs). However, fitting an RMS model to data has been infeasible due to the computational cost of simulating such shocks. We bridge the gap between theory and observation by creating an approximate but accurate model called the Kompaneets RMS approximation (KRA). In...
High energy power law spectra is common to many astronomical objects. It is often assumed that such power laws are produced by energetic particles, obtaining a power law distribution by Fermi acceleration process.Here we present a novel mechanism of generating high-energy power-law shaped spectra by repeated photon scattering off velocity shear layers in relativistic jets. This mechanism does...
The detections of photons above the pair-production threshold require the GRB outflow to be relativistic. The nature of the prompt emission (thermal or non-thermal), the jet composition, and the radius where the dissipation occurs in the outflow to produce the emission, are
uncertain. Spectral analyses of the LAT low-energy event (LLE) data of GRBs reveal a cut-off at $\lesssim$ 100 MeV. If...
Prompt emission of short gamma-ray bursts (sGRBs) are analyzed using the model of the multi-color blackbody, which is interpreted as the emission from a non-dissipative photosphere with jet structure and viewing geometry inference. Nearly 69 % and 26 % of the sample is consistent with a multicolor blackbody and a pure blackbody model, respectively. Using this physical interpretation, a narrow...
