相关论文: The Dynamics and Afterglow Radiation of Gamma-Ray …
We present the first unrestricted, three-dimensional relativistic hydrodynamical calculations of the blob of gas associated with the jet producing a gamma-ray burst. We investigate the deceleration phase of the blob corresponding to the…
Gravitational-wave detected neutron star mergers provide an opportunity to investigate short gamma-ray burst (GRB) jet afterglows without the GRB trigger. Here we show that the post-peak afterglow decline can distinguish between an…
Starting as highly relativistic collimated jets, gamma-ray burst outflows gradually decelerate and become non-relativistic spherical blast waves. Although detailed analytical solutions describing the afterglow emission received by an…
The ultra-relativistic outflows powering gamma-ray bursts (GRBs) acquire angular structure through their interaction with external material. They are often characterized by a compact, nearly uniform narrow core (with half-opening angle…
We study the morphology of gamma-ray burst (GRB) afterglows viewed off-axis using a simplified analytical model. We consider steep jets, which are expected to be the most common type. These jets, characterized by steep lateral gradients in…
The conventional derivation of the gamma-ray burst afterglow jet break time uses only the blast wave fluid Lorentz factor and therefore leads to an achromatic break. We show that in general gamma-ray burst afterglow jet breaks are chromatic…
The recently discovered GRB afterglow is believed to be described reasonably well by synchrotron emission from a slowing down relativistic shell that collides with an external medium. To compare theoretical models with afterglow…
We investigate how the angular structure of GRB jets effects the afterglow light curves at different viewing angles, $\theta_{v}$, from the jet symmetry axis. A numerical hydrodynamical modeling for the evolution of a relativistic…
Gamma-ray bursts (GRBs) are powered by ultra-relativistic jets. The launching sites of these jets are surrounded by dense media, which the jets must cross before they can accelerate and release the high energy emission. Interaction with the…
We present broad-band radio observations of the afterglow of GRB000301C, spanning from 1.4 to 350 GHz for the period of 3 to 83 days after the burst. This radio data, in addition to measurements at the optical bands, suggest that the…
We present results for a large number of gamma-ray burst (GRB) afterglow light curve calculations, done by combining high resolution two-dimensional relativistic hydrodynamics simulations using RAM with a synchrotron radiation code. Results…
We use published data in radio, optical and X-ray bands to analyze and model afterglows of GW/GRB 170817A. Our analysis is based on a phenomenological gamma-ray burst generator model which we previously used to study the prompt gamma-ray…
The jet structure in gamma-ray burst (GRB) sources is still largely an open question. The leading models invoke either (i) a roughly uniform jet with sharp edges, or (ii) a jet with a narrow core and wide wings where the energy per solid…
The CCD magnitudes in Johnson V and Cousins R and I photometric passbands are determined for GRB 000301C afterglow starting ~ 1.5 day after the gamma-ray burst. In fact we provide the earliest optical observations for this burst. Light…
A strong correlation is reported between gamma-ray burst (GRB) pulse lags and afterglow jet-break times for the set of bursts (seven) with known redshifts, luminosities, pulse lags, and jet-break times. This may be a valuable clue toward…
The detection of delayed emission at X-ray optical and radio wavelengths, ``after-glow'', suggests that the relativistic shell which emitted the initial GRB due to internal shocks decelerates on encountering an external medium, giving rise…
In this work, we have modeled the hydrodynamic evolution of the GRBs fireball in violent interaction with the external medium (the ISM) surrounding the burst source by assuming a power law distribution of the accelerated relativistic…
Gamma-ray bursts (GRBs) are the most energetic explosions in the universe, and their afterglow emission provides an opportunity to probe the physics of relativistic shock waves in an extreme environment. Several key pieces for completing…
Numerical jet simulations serve a valuable role in calculating gamma-ray burst afterglow emission beyond analytical approximations. Here we present the results of high resolution 2D simulations of decelerating relativistic jets performed…
We demonstrate that gamma-ray burst afterglow spectra and light curves can be calculated for arbitrary explosion and radiation parameters by scaling the peak flux and the critical frequencies connecting different spectral regimes. Only one…