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Related papers: Characteristic Variability Time Scales of Long Gam…

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We have investigated the time variations in the light curves from a sample of long and short Fermi/GBM Gamma ray bursts (GRBs) using an impartial wavelet analysis. The results indicate that in the source frame, the variability time scales…

High Energy Astrophysical Phenomena · Physics 2015-06-03 G. A. MacLachlan , A. Shenoy , E. Sonbas , K. S. Dhuga , B. Cobb , T. N. Ukwatta , D. C. Morris , A. Eskandarian , L. C. Maximon , W. C. Parke

The distribution of GRB durations is bimodal, but there is little additional evidence to support the division of GRBs into short and long classes. Based on simple hardness ratios, several studies have shown a tendency for longer GRBs to…

Astrophysics · Physics 2009-11-07 W. S. Paciesas , R. D. Preece , M. S. Briggs , R. S. Mallozzi

Gamma-ray bursts (GRB) are extremely energetic events and produce highly diverse light curves. Light curves are believed to be resulting from internal shocks reflecting the activities of the GRB central engine. Hence their temporal studies…

High Energy Astrophysical Phenomena · Physics 2013-07-30 P. N. Bhat

We present the results of our study of the variability time scales of a sample of 27 long Swift Gamma-Ray Bursts (GRBs) with known redshifts. The variability time scale can help our understanding of fundamental GRB parameters such as the…

High Energy Astrophysical Phenomena · Physics 2009-06-18 T. N. Ukwatta , K. S. Dhuga , W. C. Parke , T. Sakamoto , C. B. Markwardt , S. D. Barthelmy , D. F. Cioffi , A. Eskandarian , N. Gehrels , L. Maximon , D. C. Morris

Understanding the bimodal duration distribution (dynamic range $>$ 10$^{4}$) of $\gamma$-ray bursts is central to determining if the phenomenon is in fact a singular one. A unifying concept, beyond isotropy and inhomogeneity of the two…

Astrophysics · Physics 2009-10-28 J. P. Norris

We analyze a sample of bright short bursts from the BATSE 4B-catalog and find that many short bursts are highly variable ($\delta t_{min}/T\ll 1$, where $\delta t_{min}$ is the shortest pulse duration and T is the burst duration). This…

Astrophysics · Physics 2009-11-06 Ehud Nakar , Tsvi Piran

Systematic variations of average observational characteristics and correlation properties between different parameters of gamma-ray bursts (GRBs) with time from 1991 April to 1994 September are revealed. It is hard to explain the observed…

Astrophysics · Physics 2008-02-03 Ti-Pei Li

Gamma-ray bursts (GRBs) are divided into two classes according to their durations. We investigate if the softness of bursts plays a role in the conventional classification of the objects. We employ the BATSE (Burst and Transient Source…

High Energy Astrophysical Phenomena · Physics 2010-10-12 Y. -P. Qin , A. C. Gupta , J. H. Fan , C. -Y. Su , R. -J. Lu

Brightness dependent correlations have been conclusively detected in the average time profiles of gamma-ray bursts (GRBs). Determining the time constants of the stretched exponential slopes of the average peak-aligned time profile of GRBs…

Astrophysics · Physics 2009-10-30 Boris Stern , Juri Poutanen , Roland Svensson

The variety of long duration gamma-ray burst (LGRB) light curves (LCs) encode a wealth of information on how LGRB engines release energy following the collapse of the progenitor star. Attempts to characterise GRB LCs focused on a number of…

High Energy Astrophysical Phenomena · Physics 2024-05-01 C. Guidorzi , M. Sartori , R. Maccary , A. Tsvetkova , L. Amati , L. Bazzanini , M. Bulla , A. E. Camisasca , L. Ferro , F. Frontera , C. K. Li , S. L. Xiong , S. N. Zhang

We study correlations between various hardness ratios of gamma-ray bursts (GRBs) and investigate if there are any differences between the two classes of the objects in the distributions of the ratios. The results suggest that,…

Astrophysics · Physics 2009-10-31 Yi-Ping Qin , Guang-Zhong Xie , Xue-Tang Zheng , En-Wei Liang

We have analyzed the 241 bursts for which peak counts $\C$ exist in the publicly available Burst and Transient Source Experiment (BATSE) catalog. Introducing peak counts in 1024 ms as a measure of burst brightness $\B$ and the ratio of peak…

Astrophysics · Physics 2009-10-22 D. Q. Lamb , C. Graziani , I. A. Smith

Many cosmological models of gamma-ray bursts (GRBs) assume that a single relativistic shell carries kinetic energy away from the source and later converts it into gamma rays, perhaps by interactions with the interstellar medium or by shocks…

Astrophysics · Physics 2007-05-23 M. C. Sumner , E. E. Fenimore

We have investigated the bimodal distribution of the duration of BATSE gamma-ray bursts (GRBs) by analyzing light curves of 64 ms time resolution. We define the average pulse width of GRBs from the auto-correlation function of GRB profiles.…

Astrophysics · Physics 2007-05-23 Wenfei Yu , Tipei Li , Mei Wu

Gamma-ray bursts (GRBs) show a bimodal distribution of durations, separated at a duration of ~2 s. Observations have confirmed the association of long GRBs with the collapse of massive stars. The origin of short GRBs is still being…

High Energy Astrophysical Phenomena · Physics 2015-06-22 Anna Barnacka , Abraham Loeb

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

We consider whether the variability properties of Gamma-Ray Bursts (GRBs) that produce bright optical and longer wavelength transient afterglows (A-GRBs) are the same as a larger, inclusive sample of bright, long-duration GRBs, selected…

Astrophysics · Physics 2009-11-10 Joseph A. Munoz , Jonathan C. Tan

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 modified version of a bullet model for gamma ray bursts is studied. The central engine of the source produces multiple sub-jets that are contained within a cone. The emission of photons in the source frame of a sub-jet either takes part…

Astrophysics · Physics 2009-11-13 A. Janiuk , B. Czerny , R. Moderski , D. B. Cline , C. Matthey , S. Otwinowski

Gamma ray bursts (GRBs) are known to have short-time variability and power-law behavior with the index -1.67 in the power spectrum density. Reanalyzing the expanded data, we have found a) the power-law comes from the global profile of the…

Astrophysics · Physics 2009-11-06 Motoko Suzuki , Masahiro Morikawa , Izumi Joichi
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