Related papers: Magnetic Fields In Relativistic Collisionless Shoc…
We report a multi-wavelength analysis of the prompt emission and early afterglow of GRB051111 and discuss its properties in the context of current fireball models. The detection of GRB051111 by the Burst Alert Telescope on-board Swift…
We constrain the physical composition of the outflows of GRBs 080916C and 090510 with the prompt emission data and find that the former is likely magnetic while the latter may be baryonic. The X-ray and optical afterglow emission of both…
Cosmological fireball models of gamma-ray bursts (GRBs) predict delayed emission, ``after-glow,'' at longer wavelengths. We present several new results regarding the model predictions, and show that X-ray to optical observations of…
We considered a model for the prompt phase of Gamma-Ray Burst (GRB) emission arising from a magnetized jet undergoing gradual energy dissipation due to magnetic reconnection. The dissipated magnetic energy is translated to bulk kinetic…
Different forms of long gamma-ray bursts (GRBs) Luminosity Functions are considered on the basis of an explicit physical model. The inferred flux distributions are compared with the observed ones from two samples of GRBs, Swift and Fermi…
The rapid accumulation of observed Fast Radio Bursts (FRBs) originating from cosmological distances makes it likely that some will be strongly lensed by intervening matter along the line of sight. Detection of lensed FRB repeaters, which…
Simultaneous Swift and Fermi observations of gamma-ray bursts (GRBs) offer a unique broadband view of their afterglow emission, spanning more than ten decades in energy. We present the sample of X-ray flares observed by both Swift and Fermi…
(Abr) The origin and structure of magnetic fields in Gamma-Ray Burst (GRB) fireball plasmas are two of the most important open questions in all GRB models. We show that the structure and strength of the magnetic field may be constrained by…
Compact dark matter has been efficiently constrained in the M <~ 10 M_sun mass range by null searches for microlensing of stars in nearby galaxies. Here we propose to probe the mass range M >~ 10 M_sun by seeking echoes in gamma-ray-burst…
We consider a sample of ten GRBs with long lasting ($\gtrsim10^2\rm\,sec$) emission detected by Fermi/LAT and for which X-ray data around $1\,$day are also available. We assume that both the X-rays and the GeV emission are produced by…
The SN explosion in the closed binary can give the magnetospheric flare possessing the properties of GRB. The SN shock, flowing around the magnetosphere of a magnetized neutron star or a white dwarf, produces a narrow magnetic tail 10^9 cm…
The role of magnetic fields in gamma-ray burst (GRB) flows remains controversial. The study of the early afterglow phases and, in particular, of the reverse shock dynamics and associated emission offers a promising probe of the…
We present radio and optical afterglow observations of the TeV-bright long Gamma Ray Burst (GRB) 190114C at a redshift of $z=0.425$, which was detected by the MAGIC telescope. Our observations with ALMA, ATCA, and uGMRT were obtained by our…
We describe a new method to measure the escape fraction fesc of ionizing radiation from distant star-forming galaxies using the afterglow spectra of long-duration gamma-ray bursts (GRBs). Optical spectra of GRB afterglows allow us to…
FRBs constitute a unique probe of various astrophysical and cosmological environments via their characteristic dispersion and rotation (RM) measures that encode information about the ionized gas traversed by the FRB sightlines. In this…
The afterglow of the Gamma-Ray Burst (GRB) 000301C exhibited achromatic, short time-scale variability that is difficult to reconcile with the standard relativistic shock model. We interpret the observed light curves as a microlensing event…
Swift-XRT observations of the X-ray emission from gamma ray bursts (GRBs) and during the GRB afterglow have led to many new results during the past two years. One of these exciting results is that approximately 1/3-1/2 of GRBs contain…
Gamma-ray bursts (GRBs) are one of the most exciting sources that offer valuable opportunities for investigating the evolution of energy fraction given to magnetic fields and particles through microphysical parameters during relativistic…
The external forward shock (EFS) models have been the standard paradigm to interpret the broad-band afterglow data of gamma-ray bursts (GRBs). One prediction of the models is that some afterglow temporal breaks at different energy bands…
The standard external shock model in the thin-shell scenario predicts an onset bump in the early optical afterglow light curves of gamma-ray bursts (GRBs). We collect such a textbook-version light curve sample of $30$ GRBs, and derive the…