Related papers: Formation Rate, Evolving Luminosity Function, Jet …
The astrophysics of Long GRB (LGRB) progenitors as well as possible cosmological evolution in their properties still poses many open questions. Previous studies suggest that the LGRB rate density (LGRB-RD) follows the cosmic star formation…
We investigate the GRB formation rate based on the relation between the spectral peak energy ($E_{p}$) and the isotropic luminosity. The $E_{p}$--luminosity relation covers the energy range of 50 -- 2000 keV and the luminosity range of…
Originating from neutron star-neutron star (NS-NS) or neutron star-black hole (NS-BH) mergers, short gamma-ray bursts (SGRBs) are the first electromagnetic emitters associated with gravitational waves. This association makes the…
Gamma Ray Bursts (GRBs) are classified as long (LGRBs) and short (SGRBs) with collapsars and compact object mergers (neutron star (NS)-NS or NS-Black hole) as progenitors, respectively. The former are expected to follow the cosmic star…
Gamma-ray bursts (GRBs) are the most luminous electromagnetic explosions in the Universe, which emit up to $8.8\times10^{54}$ erg isotropic equivalent energy in the hard X-ray band. The high luminosity makes them detectable out to the…
Long-duration gamma-ray bursts(LGRBs) are believed to be linked with the star formation. We adopt a galactic evolution model, in which the star formation process inside the virialized dark halo at given redshift can be achieved. In this…
We present late-time Hubble Space Telescope imaging of the fields of six Swift GRBs lying at 5.0<z<9.5. Our data includes very deep observations of the field of the most distant spectroscopically confirmed burst, GRB 090423, at z=8.2. Using…
The unrivalled, extreme luminosities of gamma-ray bursts (GRBs) make them the favored beacons for sampling the high redshift Universe. To employ GRBs to study the cosmic terrain -- e.g., star and galaxy formation history -- GRB luminosities…
Spectral lag, which is defined as the difference in time of arrival of high and low energy photons, is a common feature in Gamma-ray Bursts (GRBs). Previous investigations have shown a correlation between this lag and the isotropic peak…
The determination of luminosity function (LF) of gamma-ray bursts (GRBs) is of an important role for the cosmological applications of the GRBs, which is however hindered seriously by some selection effects due to redshift measurements. In…
In this work we estimate the Star Formation Rate (SFR) through 333 Long-GRBs detected by Swift. This investigation is based on the empirical model proposed by Y\"uksel et al. (2008), basically, the SFR is estimated using long-GRBs…
We review the uncertainties in high-z star-formation rate (SFR) measures and the constraints that one obtains from high-z gamma-ray burst (GRB) rates on them. We show that at the present time, the GRB rates per unit star-formation at z>3…
We estimate the rate and the luminosity function of short (hard) Gamma-Ray Bursts (sGRBs) that are non-Collapsars, using the peak fluxes and redshifts of BATSE, Swift and Fermi GRBs. Following Bromberg2013 we select a sub-sample of Swift…
We attempt to constrain the luminosity function of Gamma Ray Bursts (GRBs) from the observed number count--flux relation and the afterglow redshift data. We assume three classes of luminosity functions for our analysis: (a) Log-normal…
The collapsar model of long gamma-ray bursts (GRBs) indicates that they may trace the star formation history. So long GRBs may be a useful tool of measuring the high-redshift star formation rate (SFR). The collapsar model explains GRB…
GRB 080913 and GRB 090423 are the most distant gamma-ray bursts (GRBs) known to-date, with spectroscopically determined redshifts of z=6.7 and z=8.1, respectively. The detection of bursts at this early epoch of the Universe significantly…
The association of some short-duration gamma-ray bursts (GRBs) with elliptical galaxies established that their progenitors, unlike those of long GRBs, belong to an old stellar population. However, the majority of short GRBs appear to occur…
We present a carefully selected sub-sample of Swift Long Gamma-ray Bursts (GRBs), that is complete in redshift. The sample is constructed by considering only bursts with favorable observing conditions for ground-based follow-up searches,…
We review the current scenario of long-duration Gamma-ray burst (LGRB) progenitors, and in addition, present models of massive stars for a mass range of $10\text{--}150 \, \mathrm{M}_\odot$ with $\Delta \mathrm{M}=10 \, \mathrm{M}_\odot$…
Gamma-ray Bursts (GRBs) are valuable probes of cosmic star formation reaching back into the epoch of reionization, and a large dataset with known redshifts ($z$) is an important ingredient for these studies. Usually, $z$ is measured using…