Related papers: Radiation Processes in GRBs. Prompt Emission
Information on the spectral shape of prompt emission in gamma-ray bursts (GRB) is mostly available only at energies $\gtrsim10$ keV, where the main instruments for GRB detection are sensitive. The origin of this emission is still very…
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…
(abridged)Prompt GRB emission is often interpreted as synchrotron radiation from high-energy electrons accelerated in internal shocks. Fast synchrotron cooling predicts that the photon index below the spectral peak is alpha=-3/2. This…
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,…
We demonstrate that the rapid spectral variability of prompt GRBs is an inherent property of radiation emitted from shock-generated, highly anisotropic small-scale magnetic fields. We interpret the hard-to-soft evolution and the correlation…
A small fraction of GRBs with available data down to soft X-rays ($\sim0.5$ keV) have been shown to feature a spectral break in the low-energy part ($\sim1-10$ keV) of their prompt emission spectrum. The overall spectral shape is consistent…
We reexamine the general synchrotron model for GRBs' prompt emission and determine the regime in the parameter phase space in which it is viable. We characterize a typical GRB pulse in terms of its peak energy, peak flux and duration and…
The radiative process responsible for gamma-Ray Burst (GRB) prompt emission has not been identified yet. If dominated by fast-cooling synchrotron radiation, the part of the spectrum immediately below the $\nu F_\nu$ peak energy should…
We discuss the prompt emission of Gamma-Ray Bursts in different spectral energy bands. First, we suggest that a three-part synchrotron emission model is a good description of the ~20 keV - 1 MeV gamma-ray emission of GRBs. We show that this…
Detection of prompt emission by Swift-XRT provides a unique tool to study how the prompt spectrum of gamma-ray bursts (GRBs) extends down to the soft X-ray band. This energy band is particularly important for prompt emission studies, since…
We discuss the prompt emission of GRBs, allowing for $\gamma\gamma$ pair production and synchrotron self-absorption. The observed hard spectra suggest heavy pair-loading in GRBs. The re-emission of the generated pairs results in the energy…
Growing evidence indicates that the synchrotron radiation mechanism may be responsible for the prompt emission of gamma-ray bursts (GRBs). In the synchrotron radiation scenario, the electron energy spectrum of the prompt emission is diverse…
We study time-resolved spectra of the prompt emission of Swift Gamma-ray bursts (GRB). Our goal is to see if previous BATSE claims of the existence of a large amount of spectra with the low energy photon indices harder than 2/3 are…
Previous studies have considered synchrotron as the emission mechanism for prompt Gamma-Ray Bursts (GRBs). These works have shown that the electrons must cool on a timescale comparable to the dynamic time at the source in order to satisfy…
For over two decades, gamma-ray burst (GRB) prompt emission spectra were modelled with smoothly-broken power laws (Band function), and a positive and tight correlation between the spectral rest-frame peak energy $E_p$ and the total…
We discuss the new surprising observational results that indicate quite convincingly that the prompt emission of Gamma-Ray Bursts (GRBs) is due to synchrotron radiation produced by a particle distribution that has a low energy cut-off. The…
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…
Motivated by the Fermi gamma-ray space telescope results, in recent years immense efforts were given to understanding the mechanism that leads to the prompt emission observed. The failure of the optically thin emission models (synchrotron…
The long-lasting tension between the observed spectra of gamma ray bursts (GRBs) and the predicted synchrotron emission spectrum might be solved if electrons do not completely cool. Evidence for incomplete cooling was recently found in…
There are two different evolution patterns of the peak energy ($E_\text{p}$) exhibited during the prompt emission phase of gamma-ray bursts (GRBs), i.e., hard-to-soft and intensity-tracking, of which the physical origin remains unknown.…