Related papers: Thermal Emission from Gamma-Ray Bursts

It is demonstrated here that if the prompt GRB emission is produced by the simplest version of the external shock model, a specific relation should prevail between the observed duration, isotropic equivalent energy, and photon peak energy.…

The pulsar wind nebula CTB 87 (G74.9+1.2) is one of the sources emitting $\gamma$-rays with energies higher than 10 TeV, as measured by the Very Energetic Radiation Imaging Telescope Array System telescope (VERITAS). In this study, we…

We investigate a scenario of photons scattering by electrons within a relativistic outflow. The outflow is composed of discrete shells with different speeds. One shell emits radiation for a short duration. Some of this radiation is…

Thermal radiation, peaking in soft X-rays, has now been detected in a handful of GRB afterglows and has to date been interpreted as shock break-out of the GRB's progenitor star. We present a search for thermal emission in the early X-ray…

Gamma-ray bursts (GRBs) show different behaviours and trends in their spectral evolution. One of the methods used to understand the physical origin of these behaviours is to study correlation between the spectral fit parameters. In this…

We review the physics of GRB production by relativistic jets that start highly opaque near the central source and then expand to transparency. We discuss dissipative and radiative processes in the jet and how radiative transfer shapes the…

Gamma-ray bursts (GRBs) are one of the most extreme transients in the universe, but their explosion and emission mechanism remains unclear. To investigate the nature of GRB jets, here we focus on X-ray flares (XFs) and extended emissions…

The emission from a gamma-ray burst (GRB) photosphere can give rise to a variety of spectral shapes. The spectrum can retain the shape of a Planck function or it can be broadened and have the shape of a Band function. This fact is best…

In the laser processing of glass, a ~50-1000 $\mu$m-thick layer of glass is heated to a high temperature by the laser beam. Due to the shallow depth of this hot layer, the infrared emission and absorption spectra may deviate from the…

We find and study a variety of the spectral-temporal behavior during the decay phase of the light curve of long and bright pulse structures in gamma-ray bursts. It was earlier found that for about half of these decays, the instantaneous…

Recently, a number of peculiar flares have been reported, which demonstrate significant non-thermal particle signatures with a low, if any, thermal emission, that implies close association of the observed emission with the primary energy…

We describe our attempt to determine if gamma-ray burst (GRB) and afterglow emissions could both arise in external shocks for simple GRBs--bursts consisting of just a few peaks in their lightcurves. We calculate peak flux and peak frequency…

A high energy power law is a common feature in the spectra of many astrophysical objects. We show that the photons in a relativistic plasma with a variable Lorentz factor go through repeated scattering with electrons to gain energy. 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…

We explore the properties of photospheric emission in the context of long gamma-ray bursts (LGRBs) using three numerical models that combine relativistic hydrodynamical simulations and Monte Carlo radiation transfer calculations in three…

I discuss the interpretation of the prompt phase in gamma-ray bursts as being dominated by quasi-thermal emission, rather than by synchrotron emission. Such an interpretation gives a more natural explanation of (i) the observed variety of…

The low-energy spectra of gamma-ray bursts' (GRBs) prompt emission are closely related to the energy distribution of electrons, which is further regulated by their cooling processes. We develop a numerical code to calculate the evolution of…

It is proposed that the prompt emission observed in bursts that exhibit a thermal component originates from relativistic radiation mediated shocks that form below the photosphere of the GRB outflow. It is argue that such shocks are expected…

Context: Despite more than half a century of research, the dominant radiation mechanism of gamma-ray burst (GRB) prompt emission remains unsolved. Some progress has been made through the analyses of the observational spectra of Swift/BAT,…

The Gamma Ray Burst (GRB) 180720B is one of the brightest events detected by the Fermi satellite and the first GRB detected by the H.E.S.S. telescope above 100 GeV. We analyse the Fermi (GBM and LAT) and Swift (XRT and BAT) data and…