Related papers: The pulse luminosity function of Swift gamma-ray b…
In order to better understand the physical origin of short duration gamma-ray bursts (GRBs), we perform time-resolved spectral analysis on a sample of 70 pulses in 68 short GRBs with burst duration $T_{90}\lesssim2$ s detected by the…
We review five studies of the gamma-ray burst (GRB) luminosity function that are based on one or more of the proposed luminosity criteria, i.e., variability, spectral lag and spectral hardness. A comparison between the resulting luminosity…
We present time-resolved spectral analysis of the steep decay segments of 29 bright X-ray flares of gamma-ray bursts (GRBs) observed with the Swift/X-ray telescope, and model their lightcurves and spectral index evolution behaviors with the…
Prompted by various analyses of long (Type II) GRB rates and their relationship to the cosmic star-formation history, metallicity and luminosity function evolution, we systematically analyze these effects with a Monte Carlo code. We test…
We present a comprehensive statistical analysis of Swift X-ray light-curves of Gamma-Ray Bursts (GRBs) collecting data from more than 650 GRBs discovered by Swift and other facilities. The unprecedented sample size allows us to constrain…
The observed redshifts and magnitudes of the host galaxies of gamma-ray bursts (GRBs) are compared with the predictions of three basic GRB models, in which the comoving rate density of GRBs is (1) proportional to the cosmic star formation…
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…
We measure the rest-frame B-band luminosity function of red-sequence galaxies (RSLF) of five intermediate-redshift (0.5 < z < 0.9), high-mass (sigma > 950 km/s) clusters. Cluster galaxies are identified through photometric redshifts based…
We analyze pulse properties of Short gamma-ray bursts (GRBs) from a new catalog containing 434 pulses from 387 BATSE Time-Tagged Event (TTE) GRBs. Short GRB pulses exhibit correlated properties of duration, fluence, hardness, and amplitude,…
Gamma-ray bursts (GRBs) offer a route to characterizing star-forming galaxies and quantifying high-$z$ star formation that is distinct from the approach of traditional galaxy surveys: GRB selection is independent of dust and probes even the…
In this paper, we study the homogeneity of the GRB distribution using a subsample of the Greiner GRB catalogue, which contains 314 objects with redshift $0<z<2.5$ (244 of them discovered by the Swift GRB Mission). We try to reconcile the…
Since the launch of Swift satellite, the detections of high-z (z>4) long gamma-ray bursts (LGRBs) have been rapidly growing, even approaching the very early Universe (the record holder currently is z=8.3). The observed high-z LGRB rate…
A large fraction of Gamma Ray Bursts (GRBs) displays an X-ray plateau phase within <10^{5} s from the prompt emission, proposed to be powered by the spin-down energy of a rapidly spinning newly born magnetar. In this work we use the…
Recent optical afterglow observations of gamma-ray bursts indicate a setting and distance scale that many relate to star-formation regions. In this paper, we use $<V/V_{max}>$ and a set of artificial trigger thresholds to probe several…
Gamma-ray bursts (GRBs) are among the most luminous explosions in the Universe and serve as powerful probes of the early cosmos. However, the rapid fading of their afterglows and the scarcity of spectroscopic measurements make photometric…
The variability of gamma-ray burst (GRB) is thought to be correlated with its absolute peak luminosity, and this relation had been used to derive an estimate of the redshifts of GRBs. Recently Amati et al. presented the results of spectral…
We compare the properties of optically dark GRBs, defined by the optical-to-X-ray spectral index beta_OX<0.5, and normal ones discovered by the Swift satellite before the year 2008 in a statistical way, using data collected from the…
We study the spectral and energetics properties of 47 long-duration gamma-ray bursts (GRBs) with known redshift, all of them detected by the Swift satellite. Due to the narrow energy range (15-150 keV) of the Swift-BAT detector, the…
The Swift spacecraft detects and autonomously observes ~100 Gamma Ray Bursts (GRBs) per year, ~96% of which are detected by the X-ray telescope (XRT). GRBs are accompanied by optical transients and the field of ground-based follow-up of…
Decades ago two classes of gamma-ray bursts were identified and delineated as having durations shorter and longer than about 2 s. Subsequently indications also supported the existence of a third class. Using maximum likelihood estimation we…