Related papers: Confronting Synchrotron Shock and Inverse Comptoni…
We present the time integrated and time resolved spectral analysis of a sample of bright bursts selected with F_{peak}>20 phot cm^{-2} sec^{-1} from the BATSE archive. We fitted four different spectral models to the pulse time integrated…
The recent simultaneous detection of optical, X-ray and gamma-ray photons from GRB990123 during the burst provides the first broadband multi-wavelength characterization of the burst spectrum and evolution. Here we show that a direct…
In this paper, we explore time resolved Gamma-Ray Burst (GRB) spectra in the context of the synchrotron emission model presented in Lloyd and Petrosian (2000; LP00). First, we show that our model - which involves three distinct emission…
In the internal shock model for gamma-ray bursts (GRBs), the synchrotron spectrum from the fast cooling electrons in a homogeneous downstream magnetic field (MF) is too soft to produce the low-energy slope of GRB spectra. However the…
We present the time integrated and time resolved spectral analysis of a sample of bright bursts selected from the BATSE archive. We fitted four different spectral models to the time integrated and time resolved spectra of the flux pulses.…
We discuss here constraints on the particle acceleration models from the observed gamma-ray bursts spectra. The standard synchrotron shock model assumes that some fraction of available energy is given instantaneously to the electrons which…
We calculate the synchrotron self-Compton emission from internal shocks occurring in relativistic winds as a source of gamma-ray bursts, with allowance for self-absorption. For plausible model parameters most pulses within a Gamma-Ray Burst…
The emission mechanism of the gamma-ray bursts (GRBs) is still a matter of debates. The standard synchrotron energy spectrum of cooling electrons F_E ~ E^{-1/2} is much too soft to account for the majority of the observed spectral slopes.…
We investigate synchrotron emission models as the source of gamma-ray burst spectra. We show that including the possibility for synchrotron self-absorption, a ``smooth cutoff'' to the electron energy distribution, and an anisotropic…
The analysis of gamma-ray burst (GRB) spectra often relies on empirical models lacking a distinct physical explanation. Previous attempts to couple physical models with observed data focus on individual burst studies, fitting models to…
I calculate spectral evolution series for pulses of GRBs, in the BATSE spectral range, for continuous particle injection and cooling by synchrotron, inverse Compton, and adiabatic expansion. The hydrodynamic properties of the relativistic…
A leading mechanism for producing cosmological gamma-ray bursts (GRBs) is via ultra-relativistic particles in an expanding fireball. The kinetic energy of the particles is converted into thermal energy in a forward shock and a reverse…
The temporal evolution of the spectral break in the time resolved spectral energy density of the broad band afterglow of gamma ray bursts (GRBs) 091127 and 080319B was shown recently to be inconsistent with that expected for the cooling…
The observational diversity of optical emission, which coincides with prompt gamma-ray bursts (GRBs), has been discovered in the recent Swift era. We show that on the assumption of the synchrotron radiation for the observed energy range…
The modelling of gamma-ray burst (GRB) spectra has considerable potential for increasing the understanding of these enigmatic sources. A diversity of ideas and analyses has been generated over the last two decades to explain line features…
We present the main results of a study of time-resolved spectra of 43 intense GRBs detected by BATSE. We considered the 4-parameter Band model and the Optically Thin Synchrotron Shock model (OTSSM). We find that the large majority of…
We aim to obtain a measure of the curvature of time-resolved spectra that can be compared directly to theory. This tests the ability of models such as synchrotron emission to explain the peaks or breaks of GBM prompt emission spectra. We…
The origin of prompt emission in $\gamma$-ray bursts (GRBs) is highly debated topic. The observed spectra are supposed to play a crucial role in constraining the location of the emitting region, the strength of the magnetic field and the…
If the emission of gamma-ray bursts were due to the synchrotron process in the standard internal shock scenario, then the typical observed spectrum should have a slope F(nu) \propto nu^{-1/2}, which strongly conflicts with the much harder…
We show that the spectral shape of the low energy tails found for the time-integrated spectra of gamma-ray bursts, even in the absence of strong synchrotron cooling, can be significantly softer than the $\nu F_\nu \propto \nu^{4/3}$…