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Related papers: Statistical analysis of RHESSI GRB database

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Intrinsic variability was searched for in arrival times of six gamma-ray bursts (GRBs) at high energies -- between 30 MeV and 2 GeV -- detected by the Fermi satellite's Large Area Telescope (LAT). The GRBs were selected from the Fermi LAT…

High Energy Astrophysical Phenomena · Physics 2024-07-31 E. Casey Aldrich , Robert J. Nemiroff

The two widely accepted classes of gamma-ray bursts (GRBs), short and long, are with confidence ascribed to mergers of compact objects and collapse of massive stars, respectively. A third, intermediate/soft class, remains putative. Its…

High Energy Astrophysical Phenomena · Physics 2019-01-23 Mariusz Tarnopolski

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

Determining the kinds of gamma-ray bursts (GRBs) has been of interest to astronomers for many years. We analyzed 1599 GRBs from the Burst and Transient Source Experiment (BATSE) 4Br catalogue using $t$-mixtures-model-based clustering on all…

High Energy Astrophysical Phenomena · Physics 2018-09-28 Souradeep Chattopadhyay , Ranjan Maitra

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…

Astrophysics · Physics 2007-05-23 J. P. Norris

It is often stated that gamma-ray bursts (GRBs) have typical energies of several hundred keV. Is this a real feature of GRBs or is it due to an observational bias? We consider the possibility that bursts of a given bolometric luminosity…

Astrophysics · Physics 2009-10-28 Tsvi Piran , Ramesh Narayan

Ever since the insightful analysis of the durations of GRBs by [Kouveliotou:93], GRBs have most often been classified into two populations: "short bursts" (shorter than 2.0 seconds) and "long bursts" (longer than 2.0 seconds). However,…

High Energy Astrophysical Phenomena · Physics 2018-10-10 Hannachi Zitouni , Nidhal Guessoum , Khalid Madjid ALQassimi , Omar Alaryani

We study the internal structural properties of 37 long duration gamma-ray burst (GRB) host galaxies imaged with the Hubble Space Telescope. Fitting exponential disk and r^1/4 models to the surface brightness profiles of eight z < 1.2 bright…

Recent evidence appears to link gamma-ray bursts (GRBs) to star-forming regions in galaxies at cosmological distances. If short-lived massive stars are the progenitors of GRBs, the rate of events per unit cosmological volume should be an…

Astrophysics · Physics 2008-11-26 Cristiano Porciani , Piero Madau

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…

High Energy Astrophysical Phenomena · Physics 2015-04-30 I. Horvath , Z. Bagoly , A. de Ugarte Postigo , L. G. Balazs , P. Veres

Earlier classification analyses found three types of gamma-ray bursts (short, long and intermediate in duration) in the BATSE sample. Recent works have shown that these three groups are also present in the RHESSI and the BeppoSAX databases.…

High Energy Astrophysical Phenomena · Physics 2015-05-18 I Horvath , Z Bagoly , LG Balazs , A de Ugarte Postigo , P Veres , A Meszaros

A long Gamma-Ray Burst (GRB) was detected with the instruments on board the INTEGRAL satellite on January 31 2003. Although most of the GRB, which lasted $\sim$150 seconds, occurred during a satellite slew, the automatic software of the…

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_{GRB}(z), using a method based on Bayesian inference. We find that, despite the qualitative…

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

We use a homogeneous sample of gamma-ray bursts (GRB) extracted from 5.9 years of BATSE DISCLA data (astro-ph/9908190) and a variety of broken power-law luminosity functions to derive GRB luminosities and space densities. Luminosity…

Astrophysics · Physics 2009-10-31 Maarten Schmidt

Two classes of Gamma-ray bursts (GRBs), corresponding to the short/hard and the long/soft events, with a putative intermediate class, are typically considered in the observer frame. However, when considering GRB characteristics in the…

A multivariate analysis of gamma-ray burst (GRB) bulk properties is presented to discriminate between distinct classes of GRBs. Several variables representing burst duration, fluence and spectral hardness are considered. Two multivariate…

In this catalog we present the updated set of spectral analyses of GRBs detected by the Fermi Gamma-Ray Burst Monitor (GBM) during its first four years of operation. It contains two types of spectra, time-integrated spectral fits and…

Gamma-Ray Bursts (GRBs) are thought to originate at cosmological distances from the most powerful explosions in the Universe. If GRBs are not beamed then the distribution of their number as a function of Gamma-ray flux implies that they…

Astrophysics · Physics 2009-10-30 Abraham Loeb , Rosalba Perna

A wavelet analysis has been performed on 80 intense gamma-ray bursts GRBs) from the BATSE 3B catalog with durations longer than 2 seconds. The wavelet analysis applied novel features developed for edge detection in image processing and this…

Astrophysics · Physics 2010-12-13 Kevin J. Hurley , Brian McBreen , Fergus Quilligan , Matt Delaney , Lorraine Hanlon

Gamma-ray bursts (GRBs) are commonly attributed to the demise of massive stars or the merger of binary compact objects. However, their varied emission characteristics strongly imply the existence of multiple GRB classes based on progenitor…

High Energy Astrophysical Phenomena · Physics 2024-07-12 Nishil Mehta , Shabnam Iyyani