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Related papers: Variability in Shell Models of Gamma-Ray Bursts

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We consider a speculative model for gamma-ray bursts (GRB), which predicts that the total kinetic energy in the ejected matter is less than the total energy in the gamma rays. There is also secondary energy in X-rays, which are emitted…

Astrophysics · Physics 2010-11-15 Saul Barshay , Georg Kreyerhoff

We study the distribution of the durations of gamma-ray bursts (GRBs) in the unified model of short and long GRBs recently proposed by Yamazaki, Ioka, and Nakamura. Monte Carlo simulations show clear bimodal distributions, with…

Astrophysics · Physics 2009-11-10 Kenji Toma , Ryo Yamazaki , Takashi Nakamura

High-energy photons of gamma-ray bursts (GRBs) might be emitted at different intrinsic times with energy dependence at the source. In this letter, we expand the model from previous works on testing the Lorentz Invariance Violation (LV) with…

High Energy Astrophysical Phenomena · Physics 2024-09-13 Hanlin Song , Bo-Qiang Ma

Gamma ray bursts (GRBs) are astronomical phenomena detected at highest energies. The gamma ray photons carry energies on the order of mega-electronovolts and arrive to us from the point-like sources that are uniformly distributed on the…

High Energy Astrophysical Phenomena · Physics 2021-04-21 A. Janiuk , B. James , K. Sapountzis

Many gamma ray bursts (GRBs) have been observed with the Burst-Alert and X-Ray telescopes of the Swift satellite. The successive `pulses' of these GRBs end with a fast decline and a fast spectral softening, until they are overtaken by…

Astrophysics · Physics 2009-11-13 Shlomo Dado , Arnon Dar , A. De Rujula

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

In order to explain the origin of skewness in the gamma-ray burst (GRB) duration distribution, a statistical model, based on the cosmological time dilation and taking into account the GRB formation rate and instrumental effects, is…

High Energy Astrophysical Phenomena · Physics 2020-07-15 Mariusz Tarnopolski

We investigate the relationship between the quasi-thermal baryon-related photosphere in relativistic outflows, and the internal shocks arising outside them, which out to a limiting radius may be able to create enough pairs to extend the…

Astrophysics · Physics 2008-11-26 P. Meszaros , E. Ramirez-Ruiz , M. J. Rees , B. Zhang

We calculate the hydrodynamic time scales for a spherical ultra-relativistic shell that is decelerated by the ISM and discuss the possible relations between these time scales and the observed temporal structure in $\gamma$-ray bursts. We…

Astrophysics · Physics 2007-05-23 Re'em Sari , Tsvi Piran

A new procedure for smoothing a gamma-ray burst (GRB) lightcurve and calculating its variability is presented. Applying the procedure to a sample of 25 long GRBs, we have obtained a very tight correlation between the variability and the…

Astrophysics · Physics 2009-11-13 Li-Xin Li , Bohdan Paczynski

In recent years, dynamical relativistic jet simulation techniques have progressed to a point where it is becoming possible to fully numerically resolve gamma-ray burst (GRB) blast-wave evolution across scales. However, the modeling of…

High Energy Astrophysical Phenomena · Physics 2021-12-15 Eliot H. Ayache , Hendrik J. van Eerten , Rupert W. Eardley

We calculate the spectra expected from unsteady relativistic wind models of gamma-ray bursts, suitable for events of arbitrary duration. The spectral energy distribution of the burst is calculated over photon energies spanning from eV to…

Astrophysics · Physics 2009-10-28 Hara Papathanassiou , Peter Meszaros

The mechanism responsible for the prompt emission of gamma-ray bursts (GRBs) is still a debated issue. The prompt phase-related GRB correlations can allow to discriminate among the most plausible theoretical models explaining this emission.…

High Energy Astrophysical Phenomena · Physics 2018-02-01 Maria Dainotti , Roberta Del Vecchio , Mariusz Tarnopolski

We calculate the hydrodynamic time scales for a spherical ultra-relativistic shell that is decelerated by the ISM and discuss the possible relations between these time scales and the observed temporal structure in $\gamma$-ray bursts. We…

Astrophysics · Physics 2009-10-28 Re'em Sari , Tsvi Piran

Gamma-ray bursts (GRBs) are the most brilliant objects in the Universe but efforts to estimate the total energy released in the explosion -- a crucial physical quantity -- have been stymied by their unknown geometry: spheres or cones. We…

Typical gamma-ray burst spectra are characterized by a spectral break, Ep, which for bright BATSE bursts is found to be narrowly clustered around 300 keV. Recently identified X-ray flashes, which may account for a significant portion of the…

Astrophysics · Physics 2009-11-07 Bing Zhang , Peter Meszaros

We discuss the possibility that gamma-ray bursts may result from cosmological relativistic blob emitting neutron star jets that precess past the line of sight. Beaming reduces the energy requirements, so that the jet emission can last…

Astrophysics · Physics 2009-10-28 Eric G. Blackman , Insu Yi , George B. Field

Gamma ray bursts (GRB's) often feature subpulses that have a distinctively asymmetric profile -- they rise quickly and decay much more slowly, while their spectrum softens slightly with observer time. It is suggested that these subpulses…

Astrophysics · Physics 2009-11-13 David Eichler , Hadar Manis

Gamma-ray bursts (GRBs) have been an enigma since their discovery forty years ago. However, considerable progress unraveling their mysteries has been made in recent years. Developments in observations, theory, and instrumentation have…

The cosmological gamma-ray burst (GRB) phenomenon is reviewed. The broad observational facts and empirical phenomenological relations of the GRB prompt emission and afterglow are outlined. A well-tested, successful fireball shock model is…

Astrophysics · Physics 2007-05-23 Bing Zhang , Peter Meszaros
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