Related papers: On the Anti-Correlation between Duration and Redsh…
Gamma-ray burst (GRB) afterglow observations have allowed us to significantly constrain the engines producing these energetic explosions. Te redshift and position information provided by these afterglows have already allowed us to limit the…
We compare the redshifts, host galaxy metallicities, and isotropic (E_gamma,iso) and beaming-corrected (E_gamma) gamma-ray energy release of 16 long-duration gamma-ray bursts (LGRBs) at z < 1. From this comparison, we find no statistically…
One of the most important task of the Gamma-Ray Burst field is the classification of the bursts. Many researches have proven the existence of the third kind (intermediate duration) of GRBs in the BATSE data. Recent works have analyzed…
Long-duration gamma-ray bursts (GRBs) are thought to come from the core-collapse of Wolf-Rayet stars. Whereas their stellar masses $M_*$ have a rather narrow distribution, the population of GRBs is very diverse, with gamma-ray luminosities…
The recent detections of bright optical/infrared kilonova signals following two long-duration gamma-ray bursts (LGRBs), GRB 211211A and GRB 230307A, have significantly challenged the traditional classification of GRBs. These merger-driven…
On 2006 May 5, a four second duration, low energy, ~10^49 erg, Gamma-Ray Burst (GRB) was observed, spatially associated with a z=0.0894 galaxy. Here, we report the discovery of the GRB optical afterglow and observations of its environment…
The duration of more than one thousand gamma-ray bursts (GRBs) has been measured by Swift satellite. Besides the redshift distribution of GRBs, the burst duration could be another significant property of GRBs that can be analyzed. In this…
Gamma Ray Bursts (GRB) are among the brightest objects in the Universe and hence can be observed up to a very high redshift. Properly calibrated empirical correlations between intensity and spectral correlations of GRBs can be used to…
We analyze a sample of 16 absorption systems intrinsic to long duration GRB host galaxies at $z \gtrsim 2$ for which the metallicities are known. We compare the relation between the metallicity and cold gas velocity width for this sample to…
The lag-luminosity relation for gamma-ray bursts (GRBs) is an anti-correlation between the time lag, tau_lag, which represents the delay between the arrival of hard and soft photons, and the isotropic peak luminosity, L. In this paper, we…
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,…
Cosmological time dilation is a fundamental phenomenon in an expanding universe, which stresses that both the duration and wavelength of the emitted light from a distant object at the redshift $z$ will be dilated by a factor of $1+z$ at the…
Gamma ray bursts have been divided into two classes, long-soft gamma ray burst and short-hard gamma ray burst according to the bimodal distribution in duration time. Due to the harder spectrum and the lack of afterglows of short-hard bursts…
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…
We study the evolution of stars that may be the progenitors of long-soft gamma-ray burst (GRBs) -- rotating naked helium stars presumed to have lost their envelopes to winds or companions. Our aim is to investigate the formation and…
There is increasingly strong evidence that gamma-ray bursts (GRBs) are associated with star-forming galaxies, and occur near or in the star-forming regions of these galaxies. These associations provide indirect evidence that at least the…
Theoretically long gamma-ray bursts (GRBs) are expected to happen in low-metallicity environments, because in a single massive star scenario, low iron abundance prevents loss of angular momentum through stellar wind, resulting in…
Gamma-ray bursts (GRBs) are ultra-relativistic collimated outflows, which emit synchrotron radiation throughout the entire electromagnetic spectrum when they interact with their environment. This afterglow emission enables us to probe the…
The progenitor stars of long Gamma-Ray Bursts (GRBs) are thought to be Wolf-Rayet stars, which generate a massive and energetic wind. Nevertheless, about 25 percent of all GRB afterglows light curves indicate a constant density medium close…
The redshift where the first stars formed is an important and unknown milestone in cosmological structure formation. The evidence linking gamma ray bursts (GRBs) with star formation activity implies that the first GRBs occurred shortly…