Related papers: Afterglows from jetted GRB remnants
We present multiwavelength observations of the afterglow of GRB 130427A, the brightest (in total fluence) gamma-ray burst of the past 29 years. Optical spectroscopy from Gemini-North reveals the redshift of the GRB to be z=0.340, indicating…
The nature of the shallow decay phase in the X-ray afterglow of the gamma-ray burst (GRB) is not yet clarified. We analyze the data of early X-ray afterglows of 26 GRBs triggered by Burst Alert Telescope onboard Neil Gehrels Swift…
We present an explanation for the unusual temporal feature of the GRB 030226 afterglow. The R-band afterglow of this burst faded as ~ t^{-1.2} in ~ 0.2 days after the burst, rebrightened during the period of ~ 0.2 - 0.5 days, and then…
The afterglow of a gamma-ray burst (GRB) is commonly thought to be due to continuous deceleration of a relativistically expanding fireball in the surrounding medium. Assuming that the expansion of the fireball is adiabatic and that the…
We calculate light-curves for Gamma-Ray Burst afterglows when material ejected in the explosion is confined to a jet which propagates in a medium with a power-law density profile. The observed light-curve decay steepens by a factor of…
We present results from extensive broadband follow-up of GRB 210204A over the period of thirty days. We detect optical flares in the afterglow at 7.6 x 10^5 s and 1.1 x 10^6 s after the burst: the most delayed flaring ever detected in a GRB…
We report on observations of a gamma-ray burst (GRB 061126) with an extremely bright (R ~ 12 mag at peak) early-time optical afterglow. The optical afterglow is already fading as a power law 22 seconds after the trigger, with no detectable…
We present a new model for the TeV afterglow of GRB 221009A. The rapid increase of the TeV flux in the very early phase is reproduced by the magnetic acceleration. We consider the change in the radial structure of the circumstellar medium…
The X-ray afterglows (AGs) of Gamma-Ray Bursts (GRBs) and X-Ray Flashes (XRFs) have, after the fast decline phase of their prompt emission, a temporal behaviour varying between two extremes. A large fraction of these AGs has a 'canonical'…
Gamma-ray burst (GRB) afterglows are well described by synchrotron emission originating from the interaction between a relativistic blast wave and the external medium surrounding the GRB progenitor. We introduce a code to reconstruct…
Gamma-ray burst afterglow observations in the Swift era have a perceived lack of achromatic jet breaks compared to the BeppoSAX era. We present our multi-wavelength analysis of GRB 060206 as an illustrative example of how inferences of jet…
Afterglows of Gamma-Ray Bursts (GRBs) are simple in the most basic model, but can show many complex features. The ultra-long duration GRB 111209A, one of the longest GRBs ever detected, also has the best-monitored afterglow in this rare…
Context. Gamma-ray burst (GRB) afterglows originate from the interaction between the relativistic ejecta and the surrounding medium. Consequently, their properties depend on several aspects: radiation mechanisms, relativistic shock…
We model the radio, optical, and X-ray emission for the afterglows of GRB 980703, 990123, 990510, and 991216, within the framework of relativistic jets, to determine their physical parameters. The models that yield acceptable fits to the…
We present the discovery of the radio afterglow of the short $\gamma$-ray burst (GRB) 210726A, localized to a galaxy at a photometric redshift of $z\sim 2.4$. While radio observations commenced $\lesssim 1~$day after the burst, no radio…
Variability on time scales \delta t < t is observed in many gamma-ray burst afterglows. It is well known that there should be no such variability if the afterglow is emitted by external shock, which is produced by the interaction of…
Gamma-ray bursts (GRBs) are fascinating extragalactic objects. They represent a fantastic opportunity to investigate unique properties not exhibited in other sources. Multi-wavelength afterglow observations from some short- and…
CCD Johnsons BV and Cousins RI photometric magnitudes are determined for 20 stars in the field of GRB 000926. Using them as calibrators, B and R band light curves are constructed of the afterglow from ours and other published observations.…
Gamma-ray burst remnants become trans-relativistic typically in days to tens of days, and they enter the deep Newtonian phase in tens of days to months, during which the majority of shock-accelerated electrons will no longer be highly…
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…