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Related papers: Gamma-Ray Bursts are Time-Asymmetric

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The time-resolved spectra of gamma-ray bursts (GRBs) remain in conflict with many proposed models for these events. After proving that most of the bursts in our sample show evidence for spectral "shape-shifting", we discuss what…

Astrophysics · Physics 2009-10-30 A. Crider , E. P. Liang , R. D. Preece

We aim to obtain high-quality time-resolved spectral fits of gamma-ray bursts (GRBs) observed by the Gamma-ray Burst Monitor (GBM) on board the Fermi Gamma-ray Space Telescope. We perform time-resolved spectral analysis with high temporal…

We suggest a connection between the pulse paradigm at gamma-ray energies and the recently demonstrated luminosity distribution in gamma-ray bursts: the spectral evolution timescale of pulse structures is anticorrelated with peak luminosity,…

Astrophysics · Physics 2009-10-31 J. P. Norris , G. F. Marani , J. T. Bonnell

Gamma-ray bursts (GRBs) have puzzled astronomers since their accidental discovery in the late sixties. The BATSE detector on the COMPTON-GRO satellite has been detecting one burst per day for the last six years. Its findings have…

Astrophysics · Physics 2009-10-31 Tsvi Piran

We report test results of the correlation between time variability and peak luminosity of Gamma-Ray Bursts (GRBs), using a larger sample (32) of GRBs with known redshift than that available to Reichart et al. (2001), and using as…

Astrophysics · Physics 2007-08-29 C. Guidorzi , F. Frontera , E. Montanari , F. Rossi , L. Amati , A. Gomboc , K. Hurley , C. G. Mundell

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

Due to their highly luminous nature, gamma-ray bursts (GRBs) are useful tools in studying the early Universe (up to z = 10). We consider whether the available subset of Swift high redshift GRBs are unusual when compared to analogous…

High Energy Astrophysical Phenomena · Physics 2013-08-27 O. M. Littlejohns , N. R. Tanvir , R. Willingale , P. T. O'Brien , P. A. Evans , A. J. Levan

We studied the complete randomness of the angular distribution of gamma-ray bursts (GRBs) detected by BATSE. Since GRBs seem to be a mixture of objects of different physical nature we divided the BATSE sample into 5 subsamples (short1,…

Astrophysics · Physics 2009-11-13 R. Vavrek , L. G. Balázs , A. Mészáros , I. Horváth , Z. Bagoly

The sky distribution of Gamma-Ray Bursts (GRBs) has been intensively studied by various groups for more than two decades. Most of these studies test the isotropy of GRBs based on their sky number density distribution. In this work we…

High Energy Astrophysical Phenomena · Physics 2017-12-25 Jakub Ripa , Arman Shafieloo

All gamma-ray bursts are observed to have approximately the same characteristic gamma-ray energy. We show in this article that for bursts in the BATSE data set, this property as measured by the E-peak value is not an instrumental effect,…

Astrophysics · Physics 2007-05-23 J. J. Brainerd , G. Pendleton , R. Mallozzi , M. S. Briggs , R. D. Preece

Gamma-ray bursts are a complex, non-linear system that evolves very rapidly through stages of vastly different conditions. They evolve from scales of few hundred kilometers where they are very dense and hot to cold and tenuous on scales of…

High Energy Astrophysical Phenomena · Physics 2015-04-10 Davide Lazzati , Brian J. Morsony , Diego López-Cámara

Gamma ray bursts (GRB) occur at random points in the sky at cosmological distances. The spectra evolve through X-ray, optical region to possibly radio frequency. Though there are some models, the origin and time evolution of GRB are not…

Astrophysics · Physics 2007-05-23 Manoj Thulasidas

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

Recent studies have found that the spectral evolution of pulses within gamma-ray bursts (GRBs) is consistent with simple radiative cooling. Perhaps more interesting was a report that some bursts may have a single cooling rate for the…

Astrophysics · Physics 2009-10-30 A. Crider , E. P. Liang , R. D. Preece

In this paper, we explore time resolved Gamma-Ray Burst (GRB) spectra in the context of the synchrotron emission model presented in Lloyd and Petrosian (2000; LP00). First, we show that our model - which involves three distinct emission…

Astrophysics · Physics 2009-11-07 Nicole M. Lloyd-Ronning , Vahe' Petrosian

The variability observed in many complex gamma-ray bursts (GRBs) is inconsistent with causally connected variations in a single, symmetric, relativistic shell interacting with the ambient material ("external shocks"). Rather, the symmetry…

Astrophysics · Physics 2009-10-30 E. E. Fenimore , C. Cooper , E. Ramirez-Ruiz , M. C. Sumner , A. Yoshida , M. Namiki

The emission mechanism of the gamma-ray bursts (GRBs) is still a matter of debates. The standard synchrotron energy spectrum of cooling electrons F_E ~ E^{-1/2} is much too soft to account for the majority of the observed spectral slopes.…

Astrophysics · Physics 2009-11-10 Boris E. Stern , Juri Poutanen

X-ray emission can provide a crucial diagnostic of gamma-ray bursts (GRBs). We calculate the X-ray and gamma-ray spectra of impulsive acceleration episodes related to GRB pulses. We use the synchrotron shock model (SSM) as a basis of our…

Astrophysics · Physics 2009-10-28 M. Tavani

We present a catalog of the redshift estimates and probability distributions for 1366 individual Long-duration Gamma-Ray Bursts (LGRBs) detected by the Burst And Transient Source Experiment (BATSE). This result is based on a careful…

High Energy Astrophysical Phenomena · Physics 2019-03-19 Amir Shahmoradi , Robert J. Nemiroff

In order to better understand the physical origin of short duration gamma-ray bursts (GRBs), we perform time-resolved spectral analysis on a sample of 70 pulses in 68 short GRBs with burst duration $T_{90}\lesssim2$ s detected by the…

High Energy Astrophysical Phenomena · Physics 2020-07-22 Hüsne Dereli-Bégué , Asaf Pe'er , Felix Ryde