Related papers: X-ray afterglow light curves : toward standard can…
We investigate the clustering of afterglow light curves observed at X-ray and optical wavelengths. We have constructed a sample of 61 bursts with known distance and X-ray afterglow. GRB sources can be divided in three classes, namely…
We studied the optical afterglows of the 24 pre-Swift Gamma-Ray Bursts with known spectroscopic redshift and published estimates of the optical extinction in the source frame. We find an unexpected clustering of the optical afterglow…
We study an extensive sample of 87 GRBs for which there are well sampled and simultaneous optical and X-ray light-curves. We extract the cleanest possible signal of the afterglow component, and compare the temporal behaviors of the X-ray…
We studied the behaviour of the optical afterglow lightcurves of a sample of 24 Gamma--Ray Bursts (GRBs) with known redshift and published estimates of the optical extinction in the source frame, detected before the SWIFT satellite launch.…
Four years after the launch the Swift satellite the nature of the GRBs broadband afterglow behaviour is still an open issue. The standard external shock fireball model cannot easily explain the combined temporal and spectral properties of…
Clustering in the luminosity of the afterglows of gamma-ray burst has been reported in the optical and X-ray. We investigate the possibility that a clustering in the luminosity of the afterglows of gamma-ray burst exists in near infrared…
We present a set of seventeen Gamma-Ray Bursts (GRBs) with known redshifts and X-ray afterglow emission. We apply cosmological corrections in order to compare their fluxes normalized at a redshift of 1. Two classes of GRB can be defined…
We collected the optical light curve data of 227 gamma-ray bursts (GRBs) observed with the TAROT, COATLI, and RATIR telescopes. These consist of 133 detections and 94 upper limits. We constructed average light curves in the observer and…
Gamma-ray bursts (GRBs) at high redshifts are expected to be gravitationally lensed by objects of different mass scales. Besides a single recent claim, no lensed GRB has been detected so far by using the gamma-ray data only. In this paper,…
We present the systematic analysis of the UVOT and XRT light curves for a sample of 26 Swift Gamma-Ray Bursts (GRBs). By comparing the optical/UV and X-ray light curves, we found that they are remarkably different during the first 500s…
A systematical study on the early X-ray afterglows of both optically bright and dark gamma-ray bursts (B-GRBs and D-GRBs) observed by Swift has been presented. Our sample includes 25 GRBs. Among them 13 are B-GRBs and 12 are D-GRBs. Our…
During the pre-Swift era, a clustering of light curves was observed in the X-ray, optical and infrared afterglow of gamma-ray bursts. We used a sample of 254 GRB X-ray afterglows to check this fact in the Swift era. We corrected fluxes for…
I discuss some theoretical expectations for the synchrotron emission from a relativistic blast-wave interacting with the ambient medium, as a model for GRB afterglows, and compare them with observations. An afterglow flux evolving as a…
We present a comparative study of the observed properties of the optical and X-ray afterglows of short- and long-duration gamma-ray bursts (GRBs). Using a large sample of 37 short and 421 long GRBs, we find a strong correlation between the…
The detection of x-ray afterglows of gamma-ray burst (GRB) sources has enabled the optical discovery that GRBs are at cosmological distances, which confirms that the enormous luminosities required must produce a relativistically expanding…
We examine a sample of 21 gamma-ray burst (GRB) afterglow light curves at radio frequencies, and compare them to the X-ray and/or optical properties of the afterglows and to the predictions of the standard jet/fireball model. Our sample…
The optical and X-ray light-curves of long Gamma Ray Bursts (GRBs) often show a complex evolution and in most cases do not track each other. This behaviour can not be easily explained by the simplest standard afterglow models. A possible…
Gamma-Ray Burst (GRB) afterglow observations in the Swift era have a perceived lack of achromatic jet breaks compared to the BeppoSAX, or pre-Swift era. Specifically, relatively few breaks, consistent with jet breaks, are observed in the…
We analyze the Swift XRT light curves and spectra of the gamma-ray bursts (GRBs) for which the redshift has been measured. The sample consists of seven GRBs. The soft X-ray light curves of all these GRBs are separated into at least two…
We present the results of a systematical analysis of the intrinsic optical afterglow light curves for a complete sample of gamma-ray bursts (GRBs) observed in the period from Feb. 1997 to Aug. 2005. These light curves are generally…