Related papers: Epeak estimator for Gamma-Ray Bursts Observed by t…
We report on the spectral cross-calibration results of the Konus-Wind, the Suzaku/WAM, and the Swift/BAT instruments using simultaneously observed gamma-ray bursts (GRBs). This is the first attempt to use simultaneously observed GRBs as a…
Instrumental selection effects can act upon the estimates of the peak energy Ep, the fluence F and the peak flux P of GRBs. If this were the case, then the correlations involving the corresponding rest frame quantities (i.e. Ep, Eiso and…
We perform a statistical analysis of the temporal and spectral properties of the latest Fermi gamma-ray bursts (GRBs) to revisit the classification of GRBs. We find that the bimodalities of duration and the energy ratio…
The recently discovered correlation between the rest frame GRB peak spectral energy $E_{\rm peak}$ and the collimation corrected energy $E_\gamma$ in long GRBs is potentially very important, yet awaits confirmation from an independent…
We report on the first completely simultaneous observation of a gamma-ray burst (GRB) using an array of Imaging Atmospheric Cherenkov Telescopes which is sensitive to photons in the very-high-energy (VHE) gamma-ray range (>~100 GeV). On…
The emission mechanism of the gamma-ray bursts (GRBs) is still a matter of debates. The standard synchrotron energy spectrum of cooling electrons F_E ~ E^{-1/2} is much too soft to account for the majority of the observed spectral slopes.…
We compare the isotropic equivalent 15-2000 keV gamma-ray energy, E_gamma, emitted by a sample of 91 swift Gamma-Ray Bursts (GRBs) with known redshifts, with the isotropic equivalent fireball energy, E_fb, as estimated within the fireball…
The average peak-aligned profile of all bursts detected by BATSE with sufficient data quality has a simple ``stretched'' exponential shape, F ~ exp[-(t/t_0)^{1/3}], where $t$ is the time measured from the time for the peak flux of the…
We compare the luminosity function and rate inferred from the GBM long bursts peak flux distribution with those inferred from the Swift and BATSE peak flux distribution. We find that the GBM, BATSE and the Swift peak fluxes can be fitted by…
A population of X-ray dominated gamma-ray bursts (GRBs) observed by Ginga, BeppoSax and Hete-2 should be represented in the BATSE data as presumably soft bursts. We have performed a search for soft GRBs in the BATSE records in the 25--100…
The long burst GRB 050717 was observed simultaneously by the Burst Alert Telescope (BAT) on Swift and the Konus instrument on Wind. Significant hard to soft spectral evolution was seen. Early gamma-ray and X-ray emission was detected by…
The variable activity of a gamma-ray burst (GRB) source is thought to be correlated with its absolute peak luminosity - a relation that, if confirmed, can be used to derive an independent estimate of the redshift of a GRB. We find that…
We study the distribution of long Gamma Ray Bursts in the Ep-Eiso and in the Ep,obs-Fluence planes through an updated sample of 76 bursts, with measured redshift and spectral parameters, detected up to September 2007. We confirm the…
We estimate the bulk Lorentz factor Gamma_0 of 31 GRBs using the measured peak time of their afterglow light curves. We consider two possible scenarios for the estimate of Gamma_0: the case of a homogeneous circumburst medium or a wind…
A time-resolved spectral analysis for a sample of 22 intense, broad GRB pulses from the BATSE GRB sample is presented. We fit the spectra with the Band function and investigate the correlation between the observed flux (F) and the peak…
The connection between Gamma-Ray Bursts (GRBs) and their afterglows is currently not well understood. Afterglow models of synchrotron emission generated by external shocks in the GRB fireball model predict emission detectable in the…
Long-duration gamma-ray bursts (GRBs) are widely believed to be highly-collimated explosions (opening angle theta ~ 1-10 deg). As a result of this beaming factor, the true energy release from a GRB is usually several orders of magnitude…
In this paper, we explore time resolved Gamma-Ray Burst (GRB) spectra in the context of the synchrotron emission model presented in Lloyd and Petrosian (2000; LP00). First, we show that our model - which involves three distinct emission…
(Shortened) GRB080319B, with an isotropic energy E_{iso}=1.32x10^{54}erg, and GRB050904, with E_{iso}=1.04x10^{54}erg, offer the possibility of studying the spectral properties of the prompt radiation of two of the most energetic Gamma-Ray…
This study presents the temporal and spectral analysis of the prompt emission of two high-redshift gamma-ray bursts (GRBs), 120521C at $z\sim6$ and 130606A at $z\sim5.91$, which were performed using the Swift-XRT/BAT and the Suzaku-WAM…