English
Related papers

Related papers: Gamma-ray burst pulse structures and emission mech…

200 papers

The dynamics of the origin of gamma-ray emissions in gamma-ray bursts (GRBs) remains an enigma. Through a joint analysis of GRB 180427A, observed by the Fermi Gamma-ray Space Telescope and AstroSat's Cadmium Zinc Telluride Imager, we…

Four years after the launch the Swift satellite the nature of the Gamma Ray Bursts (GRBs) broadband afterglow behaviour is still an open issue ad the standard external shock fireball models cannot easily explain the puzzling combined…

High Energy Astrophysical Phenomena · Physics 2009-08-05 M. Nardini , G. Ghisellini , G. Ghirlanda , A. Celotti

Most studies of quasi-periodic pulsations in solar flares have identified characteristic periods in the 5 - 300s range. Due to observational limitations there have been few attempts to probe the < 5s period regime and understand the…

Solar and Stellar Astrophysics · Physics 2024-06-12 Andrew R. Inglis , Laura A. Hayes

Employing two samples containing of 56 and 59 well-separated FRED (fast rise and exponential decay) gamma-ray burst (GRB) pulses whose spectra are fitted by the Band spectrum and Compton model, respectively, we have investigated the…

High Energy Astrophysical Phenomena · Physics 2011-02-11 Z. Y. Peng , L. Ma , X. H. Zhao , Y. Yin , L. M. Fang , Y. Y. Bao

The origin of the gamma-ray burst (GRB) prompt emission still defies explanation, in spite of recent progress made, for example, on the occasional presence of a thermal component in the spectrum along with the ubiquitous non-thermal…

High Energy Astrophysical Phenomena · Physics 2016-03-23 S. Dichiara , C. Guidorzi , L. Amati , F. Frontera , R. Margutti

There is no consensus yet on whether the precursor and the main burst of gamma-ray bursts (GRBs) have the same origin, and their jet composition is still unclear. In order to further investigate this issue, we systematically search 21 Fermi…

High Energy Astrophysical Phenomena · Physics 2024-05-27 Hui-Ying Deng , Zhao-Yang Peng , Jia-Ming Chen , Yue Yin , Ting Li

The jet compositions of gamma-ray bursts (GRBs) are very important to understand the energy dissipation and radiation mechanisms, but it remains an open question in GRB physics. In this paper, we present a systematic analysis to search for…

High Energy Astrophysical Phenomena · Physics 2026-01-09 Xue-Zhao Chang , HouJun Lü , Zhao-Wei Du , Xing Yang , En-Wei Liang

In more than four years of observation the Large Area Telescope on board the Fermi satellite has identified pulsed $\gamma$-ray emission from more than 80 young pulsars, providing light curves with high statistics. Fitting the observations…

High Energy Astrophysical Phenomena · Physics 2015-02-11 M. Pierbattista , A. K. Harding , I. A. Grenier , T. J. Johnson , P. A. Caraveo , M. Kerr , P. L. Gonthier

Most Gamma-Ray Bursts (GRBs) detected by the Fermi Gamma-ray Space Telescope exhibit a delay of up to about 10 seconds between the trigger time of the hard X-ray signal as measured by the Fermi GBM and the onset of the MeV-GeV counterpart…

High Energy Astrophysical Phenomena · Physics 2015-06-19 Gianluca Castignani , Dafne Guetta , Elena Pian , Lorenzo Amati , Simonetta Puccetti , Simone Dichiara

If gamma-ray burst prompt emission originates at a typical radius, and if material producing the emission moves at relativistic speed, then the variability of the resulting light curve depends on the viewing angle. This is due to the fact…

High Energy Astrophysical Phenomena · Physics 2016-06-28 Om S. Salafia , Gabriele Ghisellini , Alessio Pescalli , Giancarlo Ghirlanda , Francesco Nappo

It has been suggested that the prompt emission in gamma-ray bursts consists of several components giving rise to the observed spectral shape. Here we examine a sample of the 8 brightest, single pulsed {\it Fermi} bursts whose spectra are…

High Energy Astrophysical Phenomena · Physics 2016-01-27 S. Iyyani , F. Ryde , J. M. Burgess , A. Pe'er , D. B\' egué

The origins of the main burst and second burst of gamma-ray bursts (GRBs) and the composition of their jets remain uncertain. To explore this complex subject more thoroughly, we conduct a spectral analysis on 18 GRBs with a main and a…

High Energy Astrophysical Phenomena · Physics 2025-05-12 Ze-Lian Du , Zhao-Yang Peng , Jia-Ming Chen , Yue Yin , Ting Li

The time-integrated polarization degree (PD) at prompt optical band of gamma-ray burst (GRB) was predicted to be less than $20\%$, while the time-resolved one can reach as high as $75\%$ in photosphere model. Polarizations in optical band…

High Energy Astrophysical Phenomena · Physics 2024-05-13 Jia-Sheng Li , Mi-Xiang Lan , Hao-Bing Wang

A correlation is presented between the pulse lag and the jet-break time for seven BATSE gamma-ray bursts with known redshifts. This is, to our best knowledge, the first known direct tight correlation between a property of the gamma-ray…

Astrophysics · Physics 2009-11-07 Jay D. Salmonson , Titus J. Galama

We have averaged bright BATSE bursts to uncover the average overall temporal and spectral evolution of gamma-ray bursts (GRBs). We align the temporal structure of each burst by setting its duration to a standard duration, which we call…

Astrophysics · Physics 2007-05-23 E. E. Fenimore

The diverse and complex light curves of gamma-ray bursts (GRBs) remain an outstanding astrophysical mystery. Here we report the results of 2-1/2-dimensional particle-in-cell (PIC) simulations of the relativistic expansion of magnetized…

Astrophysics · Physics 2007-05-23 Edison Liang , Kazumi Nishimura

The physical origin of the >0.1 GeV emission detected from Gamma-Ray Bursts (GRBs) by the Fermi satellite has not yet been completely understood. In this work we consider the GeV light curves of ten GRBs with measured redshift detected by…

High Energy Astrophysical Phenomena · Physics 2015-06-22 L. Nava , G. Vianello , N. Omodei , G. Ghisellini , G. Ghirlanda , A. Celotti , F. Longo , R. Desiante , R. Barniol Duran

We present a comprehensive analysis of the optical and X-ray light curves (LCs) and spectral energy distributions (SEDs) of a large sample of gamma-ray burst (GRB) afterglows to investigate the relationship between the optical and X-ray…

High Energy Astrophysical Phenomena · Physics 2015-06-15 Elena Zaninoni , Maria Grazia Bernardini , Raffaella Margutti , Samantha Oates , Guido Chincarini

The temporal properties of a sample of 498 bright gamma-ray bursts (GRBs) with durations between 0.05 s and 674 s were analysed. The large range in duration (T90) is accompanied by a similarly large range in the median values of the pulse…

Astrophysics · Physics 2009-11-07 S. McBreen , B. McBreen , F. Quilligan , L. Hanlon

We present an analysis of early BAT and XRT data for 107 gamma--ray bursts (GRBs) observed by the Swift satellite. We use these data to examine the behaviour of the X-ray light curve and propose a classification scheme for GRBs based on…

Astrophysics · Physics 2008-11-26 P. T. O'Brien , R. Willingale