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Related papers: Optical observational biases in the GRB redshift

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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…

We show how the redshift and peak-flux distributions of gamma-ray bursts (GRBs) have an observation time dependence that can be used to discriminate between different burst populations. We demonstrate how observation time relations can be…

High Energy Astrophysical Phenomena · Physics 2013-02-20 E. J. Howell , D. M. Coward

Popular models for the origin of gamma-ray bursts (GRBs) include short-lived massive stars as the progenitors of the fireballs. Hence the redshift distribution of GRBs should track the cosmic star formation rate of massive stars accurately.…

Astrophysics · Physics 2009-10-31 Andrew W. Blain , Priyamvada Natarajan

I present an overview of the Swift mission, which was launched on November 20, 2004 to discover and observe the most energetic of astrophysical phenomena, gamma-ray bursts (GRBs). After almost 6 years in space the Observatory is in…

High Energy Astrophysical Phenomena · Physics 2010-10-14 P. Romano

GRB 080810 was one of the first bursts to trigger both Swift and the Fermi Gamma-ray Space Telescope. It was subsequently monitored over the X-ray and UV/optical bands by Swift, in the optical by ROTSE and a host of other telescopes and was…

Gamma-ray bursts (GRBs) are extremely powerful explosions that have been traditionally classified into two categories: long bursts (LGRBs) with an observed duration T90 > 2 s, and short bursts (SGRBs) with an observed duration T90 < 2 s,…

High Energy Astrophysical Phenomena · Physics 2024-03-25 Ali M. Hasan , Walid J. Azzam

A sample of 427 gamma-ray bursts (GRBs), measured by the RHESSI satellite, is studied statistically to determine the number of GRB groups. Previous studies based on the BATSE Catalog and recently on the Swift data claim the existence of an…

High Energy Astrophysical Phenomena · Physics 2010-04-21 J. Ripa , C. Wigger , D. Huja , R. Hudec

We present optical, near-IR, and radio follow up of sixteen Swift bursts, including our discovery of nine afterglows and a redshift determination for three. These observations, supplemented by data from the literature, provide an afterglow…

We exploit the 14 gamma-ray bursts (GRBs) with known redshifts $z$ and the 7 GRBs for which there are constraints on $z$ to determine the GRB rate $R_{\rm GRB}(z)$, using a method based on Bayesian inference. We find that, despite the…

Astrophysics · Physics 2009-11-07 Nevin Weinberg , Carlo Graziani , Donald Q. Lamb

Gamma ray Bursts (GRBs) - short bursts of few hundred keV $\gamma$-rays - have fascinated astronomers since their accidental discovery in the sixties. GRBs were ignored by most relativists who did not expect that they are associated with…

General Relativity and Quantum Cosmology · Physics 2009-10-28 Tsvi Piran

Gamma-ray bursts (GRBs) are cosmologically distributed, very energetic and very transient sources detected in the gamma-ray domain. The identification of their x-ray and optical afterglows allowed so far the redshift measurement of 150…

Astrophysics · Physics 2009-11-13 Sandra Savaglio

Gamma-ray bursts (GRBs) are tremendous explosions visible across most of the Universe, certainly out to redshifts of z=4.5 and likely out to z~10. Recently, GRBs have been found to have a roughly constant explosive energy as well as to have…

Astrophysics · Physics 2009-11-07 Bradley E. Schaefer

Gamma-ray bursts are promising tools for tracing the formation of high redshift stars, including the first generation. At very high redshifts the reverse shock emission lasts longer in the observer frame, and its importance for detection…

Astrophysics · Physics 2009-11-10 L. J. Gou , P. Meszaros , T. Abel , B. Zhang

We present science highlights and performance from the Swift X-ray Telescope (XRT), which was launched on November 20, 2004. The XRT covers the 0.2-10 keV band, and spends most of its time observing gamma-ray burst (GRB)afterglows, though…

In this work we present spectra of all $\gamma$-ray burst (GRB) afterglows that have been promptly observed with the X-shooter spectrograph until 31-03-2017. In total, we obtained spectroscopic observations of 103 individual GRBs observed…

Swift discovered the high redshift (z=6.29) GRB050904 with the Burst Alert Telescope (BAT) and began observing with its narrow field instruments 161 s after the burst onset. This gamma-ray burst is the most distant cosmic explosion ever…

We compute the luminosity function (LF) and the formation rate of long gamma ray bursts (GRBs) by fitting the observed differential peak flux distribution obtained by the BATSE experiment in two different scenarios: i) the GRB luminosity…

Astrophysics · Physics 2015-05-13 R. Salvaterra , C. Guidorzi , S. Campana , G. Chincarini , G. Tagliaferri

GRBs are now detected up to z = 8.26 . We try to find differences, in their restframe properties, which could be related either to distance or to observing conditions.

High Energy Astrophysical Phenomena · Physics 2009-12-16 G. Pizzichini , E. Maiorano , M. Genghini , F. Munz

Aims. We analyze and characterize the angular distribution of selected samples of gamma ray bursts (GRBs) from Batse and Swift data to confirm that the division in two classes of short- and long-duration GRBs correspond also to the…

Cosmology and Nongalactic Astrophysics · Physics 2010-01-15 Fabrizio Tamburini

We discuss the INTEGRAL capabilities to detect a high redshift population of gamma-ray bursts (GRBs). First a simple comparison between other past or planned experiments (BATSE, SAX, HETE-2, Romer, Swift) and INTEGRAL instrumentation (IBIS,…

Astrophysics · Physics 2007-05-23 J. Gorosabel , N. Lund , S. Brandt , N. J. Westergaard
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