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Related papers: Electromagnetic (versus fireball) model of GRBs

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The MeV spectral peak of gamma-ray bursts (GRBs) is best explained as photospheric emission from a dissipative relativistic jet. The observed non-blackbody spectrum shows that sub-photospheric dissipation involves both thermal plasma…

High Energy Astrophysical Phenomena · Physics 2016-11-07 Christoffer Lundman , Indrek Vurm , Andrei M. Beloborodov

Within the internal shock scenario we consider different mechanisms of high energy ($>1$ MeV) photon production inside a Gamma Ray Burst (GRB) fireball and derive the expected high energy photon spectra from individual GRBs during the…

Astrophysics · Physics 2009-06-23 Nayantara Gupta , Bing Zhang

The recent claim of a high degree of linear polarization in the prompt gamma-ray burst (GRB) emission of GRB 021206 might have important implications for the underlying mechanism ultimately responsible for the GRB radiation. While the claim…

Astrophysics · Physics 2007-05-23 A. Curioni , N. Mirabal

We describe our attempt to determine if gamma-ray burst (GRB) and afterglow emissions could both arise in external shocks for simple GRBs--bursts consisting of just a few peaks in their lightcurves. We calculate peak flux and peak frequency…

Astrophysics · Physics 2016-08-30 E. McMahon , P. Kumar , A. Panaitescu

(Abridged) GRB 061122 is one of the brightest GRBs detected within INTEGRAL's field of view to date. The two gamma-ray detectors on INTEGRAL were used to investigate the spectral characteristics of GRB 061122. A search for linear…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-13 S. McGlynn , S. Foley , B. McBreen , L. Hanlon , S. McBreen , D. J. Clark , A. J. Dean , A. Martin-Carrillo , R. O'Connor

The spectral properties of a composite thermal emission arising from a relativistic expanding fireball can be remarkably different from the Planck function. We perform a detailed study of such a system to explore the features of the prompt…

High Energy Astrophysical Phenomena · Physics 2024-07-04 Soumya Gupta , Sunder Sahayanathan

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

Fast radio bursts (FRBs) are millisecond transient astrophysical phenomena and bright at radio frequencies. The emission mechanism, however, remains unsolved yet. One scenario is a coherent emission associated with the magnetar flares and…

High Energy Astrophysical Phenomena · Physics 2024-01-22 Masanori Iwamoto , Yosuke Matsumoto , Takanobu Amano , Shuichi Matsukiyo , Masahiro Hoshino

Gamma-ray bursts (GRBs) are a mixed class of sources consisting of, at least, the long duration and short-hard subclasses, the X-ray flashes, and the low-luminosity GRBs. In all cases, the release of enormous amounts of energy on a short…

Astrophysics · Physics 2008-09-24 Charles D. Dermer , Chris L. Fryer

The recently detected linear polarization in the optical lightcurve of GRB 990510 renewed the interest on how polarization can be produced in gamma-ray burst fireballs. Here we present a model based on the assumption that we are seeing a…

Astrophysics · Physics 2009-10-31 Gabriele Ghisellini , Davide Lazzati

The site and mechanism of gamma-ray burst (GRB) prompt emission is still unknown. Although internal shocks have been widely discussed as the emission site of GRBs, evidence supporting other emission sites have been also suggested recently,…

Astrophysics · Physics 2015-05-13 Nayantara Gupta , Bing Zhang

We revisit the radiation mechanism of relativistic electrons in the stochastic magnetic field and apply it to the high-energy emissions of gamma-ray bursts (GRBs). We confirm that jitter radiation is a possible explanation for GRB prompt…

High Energy Astrophysical Phenomena · Physics 2011-03-28 J. Mao , J. Wang

During the last 15 years, a standard paradigm has emerged to explain both the progenitor nature and the observed radiations of gamma-ray bursts. In this work we show three GRBs for which the standard paradigm could be tested with high…

High Energy Astrophysical Phenomena · Physics 2019-08-13 B. Gendre , G. Stratta

Internal-Collision-induced Magnetic Reconnection and Turbulence (ICMART) model is a widely accepted model for explaining how high-magnetization jets produce gamma-ray burst (GRB) prompt emissions. In previous works, we show that this model…

High Energy Astrophysical Phenomena · Physics 2025-12-09 Xueying Shao , He Gao

Evidence suggests that the gamma-ray burst (GRB) ejecta is likely magnetized, although the degree of magnetization of the ejecta is unknown. We derive a rigorous analytical solution for the relativistic 90 degree shocks under the ideal MHD…

Astrophysics · Physics 2009-11-10 Bing Zhang , Shiho Kobayashi

It is demonstrated here that if the prompt GRB emission is produced by the simplest version of the external shock model, a specific relation should prevail between the observed duration, isotropic equivalent energy, and photon peak energy.…

Astrophysics · Physics 2008-11-26 Enrico Ramirez-Ruiz , Jonathan Granot

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

Gamma Ray Bursts (GRBs) are notorious for their diversity. Yet, they have a series of common features. The typical energy of their $\gamma$ rays is a fraction of an MeV. The energy distributions are well described by a ``Band spectrum'',…

Astrophysics · Physics 2009-11-10 Arnon Dar , A. De Rujula

We study the ``normal'' decay phase of the X-ray afterglows of gamma-ray bursts (GRBs), which follows the shallow decay phase, using the events simultaneously observed in the R-band. The classical external shock model -- in which neither…

The principal paradigm for gamma-ray bursts (GRBs) suggests that the prompt transient gamma-ray signal arises from multiple shocks internal to the relativistic expansion. This paper explores how GRB prompt emission spectra can constrain…

High Energy Astrophysical Phenomena · Physics 2009-06-25 Matthew G. Baring