Related papers: Gamma-Ray Bursts and Cosmology
Gamma-ray Bursts (GRBs) are bright flashes of high energy photons that can last from about 10 milliseconds to 10 minutes. Their origin and nature have puzzled the scientific community for about 25 years until 1997, when the first X-ray…
Gamma Ray Burst (GRB) afterglows close to their peak intensity are among the brightest X-ray sources in the sky. Despite their fast power-law like decay, when fluxes are integrated from minutes up to hours after the GRB event, the…
We have tested several models of GRB luminosity and redshift distribution functions for compatibility with the BATSE 4B number versus peak flux relation. Our results disagree with recent claims that current GRB observations can be used to…
We study the luminosity function (LF), the comoving rate and the detection rate of Long Gamma-Ray Burst (LGRBs) to high redshift, using galaxy catalogues constructed by combining high-resolution N-body simulations with semi-analytic models…
Gamma-ray bursts (GRBs) are detectable out to very large distances and as such are potentially powerful cosmological probes. Historically, the angular distribution of GRBs provided important information about their origin and physical…
Long gamma-ray bursts (GRBs) are the most luminous known electromagnetic radiation sources in the Universe for the 3 to 300 sec of their prompt flashes (isotropic X/ gamma-ray luminosities up to 10^53 ergs/sec). Their afterglows have first…
Gamma-ray bursts (GRBs) are the most luminous astrophysical events observed so far. They are conventionally classified into long and short ones depending on their time duration, $T_{90}$. Because of the advantage their high redshifts offer,…
The cosmic gamma-ray burst (GRB) formation rate, as derived from the variability-luminosity relation for long-duration GRBs, is compared with the cosmic star formation rate. If GRBs are related to the collapse of massive stars, one expects…
The class of long gamma-ray bursts (LGRBs) is associated with the collapse of the most massive stars, making them a tool to investigate star formation in the early Universe. Furthermore, thanks to their exceptional brightness, LGRB…
The nature of Gamma Ray Bursts (GRBs) remains a complete mystery, despite the recent breakthrough discovery of low energy counterparts, although it is now generally believed that at least most GRBs are at cosmological distances. Virtually…
The most energetic gamma-ray bursts (GRBs) are remarkable sources releasing huge amounts of energy on short timescales. Their prompt emission, which usually lasts few seconds, is so bright that it is visible across the whole observable…
Gamma-Ray Bursts (GRBs) are unique probes of the cosmic star formation history and the state of the intergalactic medium up to the redshifts of the first stars. In particular, the ongoing {\it Swift} mission might be the first observatory…
Context. Gamma-ray bursts (GRBs), observed at redshifts as high as 9.4, could serve as valuable probes for investigating the distant Universe. However, this necessitates an increase in the number of GRBs with determined redshifts, as…
Gamma-ray bursts (GRBs) by virtue of their high luminosities can be detected up to very high redshifts and therefore can be excellent probes of the early universe. This task is hampered by the fact that most of their characteristics have a…
Gamma-ray bursts (GRBs) and their afterglows have been proposed as an excellent probe to study the evolution of cosmic star formation, the reionization of the intergalactic medium, and the metal enrichment history of the universe, since the…
In an effort to understand the puzzle of classifying gamma-ray bursts (GRBs), we perform a systematic study of {\it Swift} GRBs and investigate several short GRB issues. Though short GRBs have a short ($\lesssim2$ s) prompt duration as…
The prompt emission mechanism of gamma-ray bursts (GRB) even after several decades remains a mystery. However, it is believed that correlations between observable GRB properties given their huge luminosity/radiated energy and redshift…
Gamma-ray bursts (GRBs), which have isotropic energy up to $10^{54}$ erg, would be the ideal tool to study the properties of early universe: including dark energy, star formation rate, and the metal enrichment history of the Universe. We…
We show that, if many GRBs are indeed produced by the collapse of massive stars, GRBs and their afterglows provide a powerful probe of the very high redshift (z > 5) universe.
Gamma-Ray Bursts (GRBs) are believed to originate in compact remnants (black holes or neutron stars) of massive stars. Their high luminosities make them detectable out to the edge of the visible universe. We describe the many advantages of…