English
Related papers

Related papers: Variability Time Scales of Long and Short GRBs

200 papers

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 2015-06-12 Narayana P. Bhat

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

We develop a robust technique to determine the minimum variability timescale for Gamma-ray Burst light curves, utilizing Haar wavelets. Our approach averages over the data for a given GRB, providing an aggregate measure of signal variation…

High Energy Astrophysical Phenomena · Physics 2015-06-19 V. Zach Golkhou , Nathaniel R. Butler

Context. Gamma-ray bursts (GRBs) have traditionally been classified by duration into long (LGRBs) and short (SGRBs), with the former believed to originate from massive star collapses and the latter from compact binary mergers. However,…

High Energy Astrophysical Phenomena · Physics 2025-10-15 R. Maccary , C. Guidorzi , A. E. Camisasca , M. Maistrello , S. Kobayashi , L. Amati , L. Bazzanini , M. Bulla , L. Ferro , F. Frontera , A. Tsvetkova

The dissipation process of GRB prompt emission is still unknown. Study of temporal variability may provide a unique way to discriminate the imprint of the inner engine activity from geometry and propagation related effects. We define the…

The light curves of Gamma-Ray Bursts (GRBs) are believed to result from internal shocks reflecting the activity of the GRB central engine. Their temporal deconvolution can reveal potential differences in the properties of the central…

We have developed a computer model to calculate gamma ray burst (GRB) light curves and efficiencies from the interaction of a single, thin blast wave with clouds in the external medium. Large amplitude, spiky variability occurs when the…

Astrophysics · Physics 2009-10-31 Charles D. Dermer , Kurt E. Mitman

The minimum variability timescale (MVT) is a key observable used to probe the central engines of Gamma-Ray Bursts (GRBs) by constraining the emission region size and the outflow Lorentz factor. However, its interpretation is often…

High Energy Astrophysical Phenomena · Physics 2026-02-13 S. Bala , P. Veres , A. Goldstein , R. Sonawane , R. Samanta , S. Iyyani

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 nature of the `inner engine' that accelerate and collimate the relativistic flow at the cores of GRBs is the most interesting current puzzle concerning GRBs. Numerical simulations have shown that the internal shocks' light curve…

Astrophysics · Physics 2009-11-07 E. Nakar , T. Piran

Gamma-ray bursts (GRBs) are promising as sources of neutrinos and cosmic rays. In the internal shock scenario, blobs of plasma emitted from a central engine collide within a relativistic jet and form shocks, leading to particle acceleration…

High Energy Astrophysical Phenomena · Physics 2017-06-06 Mauricio Bustamante , Jonas Heinze , Kohta Murase , Walter Winter

A popular paradigm to explain the rapid temporal variability observed in gamma-ray burst (GRB) lightcurves is the internal shock model. We propose an alternative model in which the radiating fluid in the GRB shell is relativistically…

Astrophysics · Physics 2009-11-13 Ramesh Narayan , Pawan Kumar

Randomly oriented relativistic emitters in a relativistically expanding shell provides an alternative to internal shocks as a mechanism for producing GRBs' variable light curves with efficient conversion of energy to radiation. In this…

High Energy Astrophysical Phenomena · Physics 2015-05-13 Ayah Lazar , Ehud Nakar , Tsvi Piran

The minimum variation timescale (MVT) of soft gamma-ray repeaters can be an important probe to estimate the emission region in pulsar-like models, as well as the Lorentz factor and radius of the possible relativistic jet in gamma-ray burst…

At the dawn of the gamma-ray burst (GRB) afterglow era, a Cepheid-like correlation was discovered between time variability V and isotropic-equivalent peak luminosity Liso of the prompt emission of about a dozen long GRBs with measured…

The complete high-resolution lightcurves of Swift GRB 080319B present an opportunity for detailed temporal analysis of the prompt optical emission. With a two-component distribution of initial Lorentz factors, we simulate the dynamical…

High Energy Astrophysical Phenomena · Physics 2015-06-17 Si-Yao Xu , Zhuo Li

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 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

In the external shock model, gamma-ray burst (GRB) emissions are produced by the energization and deceleration of a thin relativistic blast wave due to its interactions with the circumburst medium (CBM). We study the physical properties of…

Astrophysics · Physics 2009-10-31 Charles D. Dermer , Markus Boettcher , J. Chiang

We determined the characteristic variability time scales (\Delta t_p) of 410 bright and long GRBs, by locating the peaks of their Power Density Spectra, defined and calculated in the time domain. We found that the averaged variability time…

Astrophysics · Physics 2015-06-24 R. F. Shen , L. M. Song
‹ Prev 1 2 3 10 Next ›