Related papers: The X-ray afterglow of GRB 081109A: clue to the wi…

We present broad-band observations of the afterglow and environment of the short GRB 111020A. An extensive X-ray light curve from Swift/XRT, XMM-Newton and Chandra, spanning ~100 seconds to 10 days after the burst, reveals a significant…

The short/hard GRB051210 was detected and located by the Swift-BAT instrument and rapidly pointed towards by the narrow field instrumens. The XRT was able to observe a bright X-ray afterglow, one of the few ever observed for this class of…

We study the evolution of the circumstellar medium of massive stars. We pay particular attention to Wolf-Rayet stars that are thought to be the progenitors of some long Gamma-Ray Bursts. We detail the mass-loss rates we use in our stellar…

We revisit the physical origin of the achromatic peaks and breaks observed several thousand seconds after the burst in the multi-wavelength afterglows of XRF 080330 and GRB 080710. Using a numerical afterglow model that consistently…

GRB 050730 is a long duration high-redshift burst (z=3.967) discovered by Swift. The afterglow shows variability and is well monitored over a wide wavelength range. We present comprehensive temporal and spectral analysis of the afterglow of…

The behaviour of the afterglow (AG) of gamma-ray bursts (GRBs) directly provides, in the cannonball (CB) model, information about the environment of their progenitor stars. The well observed early temporal decline of the AG of GRB 021211 is…

The Swift era has posed a challenge to the standard blast-wave model of Gamma Ray Burst (GRB) afterglows. The key observational features expected within the model are rarely observed, such as the achromatic steepening (`jet-break') of the…

We present an analysis of the unusual optical light curve of the gamma-ray burst GRB~081029, which occurred at a redshift of z = 3.8479$. We combine X-ray and optical observations from the Swift X-Ray Telescope and the Swift…

Gamma-ray bursts (GRBs) are powerful probes of early stars and galaxies, during and potentially even before the era of reionization. Although the number of GRBs identified at z>6 remains small, they provide a unique window on typical…

We present extensive multi-colour (UBVR_CI_C) photometry of the optical afterglow of GRB 980519. Upon discovery, 8.3 hours after the burst, the source was decaying as a power law, (t-t_GRB)^alpha, with a rapid decay rate alpha_1 = -…

We present a detailed broadband afterglow study of GRB 220101A ($10^4\lesssim\Delta T\lesssim10^7$ s) combining multi-wavelength data from soft X-rays until 6 GHz. The afterglow light curves in both X-ray and optical show distinct…

GRB 080810 was one of the first bursts to trigger both Swift and the Fermi Gamma-ray Space Telescope. It was subsequently monitored over the X-ray and UV/optical bands by Swift, in the optical by ROTSE and a host of other telescopes and was…

We present a systematic temporal and spectral study of all Swift-XRT observations of GRB afterglows discovered between 2005 January and 2007 December. After constructing and fitting all light curves and spectra to power-law models, we…

We present a detailed analysis of Swift multi-wavelength observations of GRB 070110 and its remarkable afterglow. The early X-ray light curve, interpreted as the tail of the prompt emission, displays a spectral evolution already seen in…

We report the results of the Swift and XMM observations of the Swift-discovered long Gamma-Ray Burst GRB 060729 ($T_{90}$=115s). The afterglow of this burst was exceptionally bright in X-rays as well as at UV/Optical wavelengths showing an…

We have conducted a thorough and blind search for emission lines in >70 Swift X-ray afterglows of total exposure ~10^7s. We find that most afterglows are consistent with pure power-laws plus extinction. Significant outliers to the…

Gamma-ray bursts (GRBs) are generally believed to occur in environments where the surrounding medium is either a uniform interstellar medium (ISM) or, in some cases, a dense stellar wind from a massive progenitor. Recently, GRB 191019A has…

We report the simultaneous observations of the prompt emission in the gamma-ray and hard X-ray bands by the Swift-BAT and the KONUS-Wind instruments of the short-hard burst, GRB 060313. The observations reveal multiple peaks in both the…

We present a multiwavelength study of GRB 151027A. This is the 999th GRB detected by the Swift satellite and it has a densely sampled emission in the X-ray and optical band and has been observed and detected in the radio up to 140 days…

In this paper, we model the dynamics and radiation physics of the rarity event GRB 221009A afterglow in detail. By introducing a top-hat jet that propagates in an environment dominated by stellar winds, we explain the publicly available…