Related papers: Pulse Structure of Hot Electromagnetic Outflows wi…
A popular paradigm to explain the rapid temporal variability observed in gamma-ray burst (GRB) lightcurves is the internal shock model. We propose an alternative model in which the radiating fluid in the GRB shell is relativistically…
Gamma-ray bursts (GRBs) are a mixed class of sources consisting of, at least, the long duration and short-hard subclasses, the X-ray flashes, and the low-luminosity GRBs. In all cases, the release of enormous amounts of energy on a short…
Gamma-Ray Bursts (GRBs), short and intense pulses of low energy gamma-rays, have fascinated astronomers and astrophysicists since their unexpected discovery in the late sixties. During the last decade, several space missions: BATSE (Burst…
The Gamma-Ray Bursts (GRBs) offer the unprecedented opportunity to observe for the first time the blackholic energy extracted by the vacuum polarization during the process of gravitational collapse to a black hole leading to the formation…
(Abridged) We interpret gamma ray bursts as relativistic, electromagnetic explosions. Specifically, we propose that they are created when a rotating, relativistic, stellar-mass progenitor loses much of its rotational energy in the form of a…
Robust generation of gamma-ray bursts (GRBs) implies the formation of outflows with very low baryon loads and highly relativistic velocities, but more baryon-rich, slower outflows are also likely to occur in most GRB central engine…
Gamma-ray bursts (GRB) are short and intense bursts of $\sim$100 keV$-$1MeV photons, usually followed by long-lasting decaying afterglow emission in a wide range of electromagnetic wavelengths from radio to X-ray and, sometimes, even to GeV…
The temporal properties of a sample of 498 bright gamma-ray bursts (GRBs) with durations between 0.05 s and 674 s were analysed. The large range in duration (T90) is accompanied by a similarly large range in the median values of the pulse…
The origin of prompt emission in GRBs is not yet well understood. The simplest and most popular model is Synchrotron, Self-Compton (SSC) emission produced by internal shocks inside an ultra-relativistic jet. However, recent observations of…
In the external shock model, gamma-ray burst (GRB) emissions are produced by the energization and deceleration of a thin relativistic blast wave due to its interactions with the circumburst medium (CBM). We study the physical properties of…
Currently, the best available probe of the early phase of gamma-ray burst (GRB) jet attributes is the prompt gamma-ray emission, in which several intrinsic and extrinsic variables determine GRB pulse evolution. Bright, usually complex…
The energy dissipation mechanism within Gamma-Ray Burst (GRB) outflows, driving their extremely luminous prompt $\gamma$-ray emission is still uncertain. The leading candidates are internal shocks and magnetic reconnection. While the…
Gamma-ray bursts (GRBs) are luminous stellar explosions characterized by the ejection of relativistic jets. This work proposes a novel paradigm to study these GRB jets. By analyzing the timing information of prompt pulses and X-ray flares,…
The discovery (Liang & Kargatis 1996), that the peak energy of time-resolved spectra of gamma-ray burst (GRB) pulses decays exponentially with fluence, is analytically shown to imply that the time-integrated photon number spectrum of a…
We propose to identify pulsar-wind bubbles (PWBs) as the environment in which the afterglow emission in at least some gamma-ray bursts (GRBs) originates. Such bubbles could naturally account for the high fraction of the internal energy…
In many models of Gamma-Ray Bursts (GRBs) relativistic shells are responsible for the overall envelope of emission. We use kinematics and symmetry to calculate the time history and spectral evolution expected from a relativistic shell…
The origin of magnetic fields that permeate the blast waves of gamma-ray bursts (GRBs) is a long-standing problem. The present paper argues that in four GRBs revealing extended emission at >100 MeV, with follow-up in the radio, optical and…
Gamma-ray bursts (GRBs) are bright extragalactic flashes of gamma-ray radiation and briefly the most energetic explosions in the Universe. Their catastrophic origin (the merger of compact objects or the collapse of massive stars) drives the…
Several patterns have been discovered in how some spectral characteristics change during the decaying phase of long (> few s.) GRB pulses. We compare these observed signatures with those expected from a relativistically expanding shell.…
I consider a model of GRBs where they arise right before the merging of binary pulsars. Binary pulsars moving through the companion's magnetic field experience a large, motional electric field $\vec{E}=\vec{v}\wedge\vec{B}/c$, which leads…