Related papers: Implication of Temporal Structure in GRB
Gamma-ray burst (GRB) engines are probed most intimately during the prompt gamma-ray luminous phase when the expanding blast wave is closest to the explosion center. Using GRBs 990123 and 940217 as guides, we briefly review observations of…
Massive stars lose a large fraction of their original mass over the course of their evolution. These stellar winds shape the surrounding medium according to parameters that are the result of the characteristics of the stars, varying over…
Gamma-ray bursts are believed to originate from internal shocks which arise in an irregular relativistic wind. The process has been thought to be inefficient, converting only a few percent of the kinetic energy into gamma-rays. We define…
Long-duration gamma-ray bursts (GRBs) have been often considered as the natural evolution of some core-collapse supernovae (SNe). While GRBs with relativistic jets emit an electromagnetic signal, GRBs with mildly relativistic jets are…
This paper presents the theoretical basis of the fireball/blast wave model, and some implications of recent results on GRB source models and cosmic-ray production from GRBs. BATSE observations of the prompt gamma-ray luminous phase, and…
When does a GRB stop and its afterglow begin? A GRB may be defined as emission by internal shocks and its afterglow as emission by an external shock, but it is necessary to distinguish them observationally. With these definitions…
We assess two mechanisms to produce a short GRB from a neutron star coalescence: the annihilation of neutrino and anti-neutrino pairs and magnetic processes within the remnant. We find that the neutrino-driven wind from the remnant can…
X-ray afterglow light curves have been collected for over 400 Swift gamma-ray bursts with nearly half of them having X-ray flares superimposed on the regular afterglow decay. Evidence suggests that gamma-ray prompt emission and X-ray flares…
In the popular internal shock model for the prompt emission of gamma-ray bursts (GRBs), collisions between a series of relativistic shells generate lots of paired forward and reverse shocks. We show that the synchrotron emission produced by…
We present a simple, semi-analytical model to explain GRB temporal and spectral properties in the context of the internal shock model. Each individual pulse in the temporal profiles is produced by the deceleration of fast moving material by…
We argue that a nonthermally looking spectrum of a gamma-ray burst (GRB) can be formed as a superposition of a set of thermal blackbody spectra. This superposition may be done by time integration which is present even in `time resolved' GRB…
Gamma-ray bursts (GRBs) are presumed to be powered by still unknown central engines for the timescales in the range $1ms \sim$ a few s. We propose that the GRB central engines would be a viable site for strong meson synchrotron emission if…
Central engine of gamma-ray bursts (GRBs) may be intermittent and launch several episodes of ejecta separated by a long quiescent interval. In this scenario, an external shock is formed due to the propagation of the first launched ejecta…
We present the main observational features expected for GRBs that occur inside pulsar wind bubbles (PWBs). This is the most natural outcome of supranova model where initially a supernova explosion takes place, leaving a supra-massive NS,…
A variety of arguments suggest that the most common form of gamma-ray bursts (GRBs), those longer than a few seconds, involve the formation of black holes in supernova-like events. Two kinds of ``collapsar'' models are discussed, those in…
We consider a speculative model for gamma-ray bursts (GRB), which predicts that the total kinetic energy in the ejected matter is less than the total energy in the gamma rays. There is also secondary energy in X-rays, which are emitted…
Sari and Piran have demonstrated that the time structure of gamma-ray bursts must reflect the time structure of their energy release. A model which satisfies this condition uses the electrodynamic emission of energy by the magnetized…
Recently, a short-duration GRB with supernova association (GRB 200826A) and two long-duration GRBs with kilonova associations (GRB 211211A and GRB 230307A) have been detected, which demolished the hope for a tidy connection between GRB…
Striking similarities exist between high energy gamma ray emission from active galactic nuclei (AGN) and gamma ray bursts (GRBs). They suggest that GRBs are generated by inverse Compton scattering from highly relativistic electrons in…
Gamma-ray bursts (GRBs) are violent explosions, coming from cosmological distances. They are detected in gamma-rays (also X-rays, UV, optical, radio) almost every day, and have typical durations of a few seconds to a few minutes. Some GRBs…