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Related papers: Anomalies in the GRB spatial distribution

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In this letter, we calculate the redshift distribution of gamma-ray bursts assuming that they trace (i) the globally averaged star formation rate or (ii) the average metallicity in the Universe. While at redshifts 5 and below, both the star…

The redshift distribution of gamma-ray bursts collected in the BATSE Catalog is compared with the star formation rate. We aim to clarify the accordance between them. We also study the case of comoving number density of bursts monotonously…

Astrophysics · Physics 2009-11-11 A. Meszaros , Z. Bagoly , L. G. Balazs , I. Horvath

We present 10 new gamma-ray burst (GRB) redshifts and another five redshift limits based on host galaxy spectroscopy obtained as part of a large program conducted at the Very Large Telescope (VLT). The redshifts span the range 0.345 < z <…

Cosmology and Nongalactic Astrophysics · Physics 2012-05-31 P. Jakobsson , J. Hjorth , D. Malesani , R. Chapman , J. P. U. Fynbo , N. R. Tanvir , B. Milvang-Jensen , P. M. Vreeswijk , G. Letawe , R. L. C. Starling

We study the redshift space correlation function of galaxy clusters for observational samples constructed in different surveys. We explore correlation amplitudes, pairwise velocity distributions and bias factors. Systematics in cluster…

Astrophysics · Physics 2009-11-07 N. D. Padilla , D. G. Lambas

We construct the Hubble diagram (HD) of Gamma-Ray Bursts (GRBs) with redshifts reaching up to $z \sim 6$, by using five luminosity vs. luminosity indicator relations calibrated with the Cardassian cosmology. This model has a major…

Astrophysics · Physics 2011-05-24 Herman J. Mosquera Cuesta , Habib Dumet M. , Cristina Furlanetto

A recent spectrum of the optical afterglow of GRB 970508 suggests that gamma-ray bursts (GRBs) are cosmological in origin and it is of crucial importance to derive an accurate distance to each burst. If GRBs occur near their host galaxies…

To date, the Burst Alert Telescope (BAT) onboard Swift has detected ~ 1000 gamma-ray bursts (GRBs), of which ~ 360 GRBs have redshift measurements, ranging from z = 0.03 to z = 9.38. We present the analyses of the BAT-detected GRBs for the…

The high-redshift gamma-ray bursts (GRBs), GRBs 080913 and 090423, challenge the conventional GRB progenitor models by their short durations, typical for short GRBs, and their high energy releases, typical for long GRBs. Meanwhile, the GRB…

High Energy Astrophysical Phenomena · Physics 2014-11-21 K. S. Cheng , Yun-Wei Yu , T. Harko

Decades ago two classes of gamma-ray bursts were identified and delineated as having durations shorter and longer than about 2 s. Subsequently indications also supported the existence of a third class. Using maximum likelihood estimation we…

High Energy Astrophysical Phenomena · Physics 2016-04-27 I. Horvath , B. G. Toth

The physics of gamma-ray bursts (GRBs) and their offsets from the centers of their host galaxies are used to investigate the evolutionary state of their progenitors, motivated by the popular idea that GRBs are linked with the cataclysmic…

Astrophysics · Physics 2009-11-07 Enrico Ramirez-Ruiz , Davide Lazzati , Andrew W. Blain

We present deep optical and near-infrared observations of the host galaxies of 34 fast radio bursts (FRBs) detected by the Commensal Real-time ASKAP Fast Transient (CRAFT) survey on the Australian SKA Pathfinder (ASKAP) to compare the…

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…

High Energy Astrophysical Phenomena · Physics 2015-05-19 M. A. Campisi , L. -X. Li , P. Jakobsson

The study of the rest frame properties of long Gamma-Ray bursts (GRBs) afterglows is a fundamental aspect for a better understanding of the nature of these powerful explosions. The launch of the Swift satellite (November 2004) marked a…

High Energy Astrophysical Phenomena · Physics 2009-08-03 M. Nardini , G. Ghisellini , G. Ghirlanda

Abundances of galaxies at redshifts z > 4 are difficult to obtain from damped Ly {\alpha} (DLA) systems in the sightlines of quasars (QSOs) due to the Ly {\alpha} forest blanketing and the low number of high-redshift quasars detected.…

We present observations and analysis of the host galaxies of 23 heavily dust-obscured gamma-ray bursts (GRBs) observed by the Swift satellite during the years 2005-2009, representing all GRBs with an unambiguous host-frame extinction of…

The number of long gamma-ray bursts (GRBs) known to have occurred in the distant Universe (z greater than 5) is small (approx 15), however these events provide a powerful way of probing star formation at the onset of galaxy evolution. In…

We observe strong correlations between the temporal properties of gamma ray bursts (GRBs) and their apparent peak brightness. The strongest effect (with a significance level of 10^{-6}) is the difference between the brightness distributions…

Astrophysics · Physics 2011-07-13 Boris Stern , Juri Poutanen , Roland Svensson

A sample of 286 gamma-ray bursts (GRBs) detected by the Swift satellite and 358 GRBs detected by the RHESSI satellite are studied statistically. Previously published articles, based on the BATSE GRB Catalog, claimed the existence of an…

High Energy Astrophysical Phenomena · Physics 2015-05-14 J. Ripa , D. Huja , A. Meszaros , R. Hudec , W. Hajdas , C. Wigger

The best measure of the Universe should be done using a standard "ruler" at any redshift. Type Ia Supernovae (SN Ia) probe the universe up to z$\sim$1.5, while the Cosmic Microwave Background (CMB) primary anisotropies concern basically…

Astrophysics · Physics 2009-11-10 G. Ghirlanda , G. Ghisellini , D. Lazzati , C. Firmani

For a few seconds a gamma-ray burst (GRB) becomes the brightest object in the Universe, over-shining the rest of the Universe combined! Clearly this reflects extreme conditions that are fascinating and worth exploring. The recent discovery…

Astrophysics · Physics 2009-09-25 Tsvi Piran
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