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Related papers: Temporal Evolution of Prompt GRB Polarization

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Linear and circular polarizations of gamma-ray bursts (GRBs) have been detected during recent years. We adopt a simplified model to investigate GRB polarization characteristics in this paper. A compressed two-dimensional turbulent slab…

High Energy Astrophysical Phenomena · Physics 2017-04-19 Jirong Mao , Jiancheng Wang

There are two different evolution patterns of the peak energy ($E_\text{p}$) exhibited during the prompt emission phase of gamma-ray bursts (GRBs), i.e., hard-to-soft and intensity-tracking, of which the physical origin remains unknown.…

High Energy Astrophysical Phenomena · Physics 2021-12-20 Hao-Xuan Gao , Jin-Jun Geng , Yong-Feng Huang

The degree and the temporal evolution of linear polarization in the prompt and afterglow emission of gamma-ray bursts is a very robust diagnostic of some key features of gamma-ray bursts jets and their micro and macro physics. In this…

High Energy Astrophysical Phenomena · Physics 2016-06-01 Davide Lazzati

Polarization can serve as a probe of the radiation mechanism and magnetic field (MF) configuration in gamma-ray bursts (GRBs). In the case of constant MF, the synchrotron polarization in the prompt phase of GRBs has been widely studied. In…

High Energy Astrophysical Phenomena · Physics 2020-09-30 K. F. Cheng , X. H. Zhao , J. M. Bai

The prompt emission phase of gamma-ray bursts (GRBs) exhibits two distinct patterns of the peak-energy ($E_p$) evolution, i.e., time-resolved spectral analyses of $\nu F_{\nu}$ spectra of broad pulses reveal (1) "hard-to-soft" and (2)…

High Energy Astrophysical Phenomena · Physics 2018-12-26 Z. Lucas Uhm , Bing Zhang , Judith Racusin

We demonstrate that the rapid spectral variability of prompt GRBs is an inherent property of radiation emitted from shock-generated, highly anisotropic small-scale magnetic fields. We interpret the hard-to-soft evolution and the correlation…

Astrophysics · Physics 2009-11-11 Mikhail V. Medvedev

The radiation mechanisms powering Gamma-ray bursts (GRBs) and their physical processes remain one of the unresolved questions in high-energy astrophysics. Spectro-polarimetric observations of exceptionally bright GRBs provide a powerful…

Internal shocks are a leading candidate for the dissipation mechanism that powers the prompt $\gamma$-ray emission in gamma-ray bursts (GRBs). In this scenario a compact central source produces an ultra-relativistic outflow with varying…

High Energy Astrophysical Phenomena · Physics 2023-12-25 Sk. Minhajur Rahaman , Jonathan Granot , Paz Beniamini

Synchrotron circular polarization of a non-thermal power-law electron distribution in gamma-ray bursts (GRBs) has been studied. However, some numerical simulations have shown that the resulting distribution of electrons is a combination of…

High Energy Astrophysical Phenomena · Physics 2025-05-29 Kangfa Cheng , Jirong Mao , Xiaohong Zhao , Hongbang Liu , Zhegeng Chen , Gaojin Yu , Zhifu Chen

Motivated by the Fermi gamma-ray space telescope results, in recent years immense efforts were given to understanding the mechanism that leads to the prompt emission observed. The failure of the optically thin emission models (synchrotron…

High Energy Astrophysical Phenomena · Physics 2015-06-16 Asaf Pe'er

The detection of delayed X-ray, optical and radio emission, "afterglow", associated with $\gamma$-ray bursts (GRBs) is consistent with fireball models, where the emission are produced by relativistic expanding blast wave, driven by…

Astrophysics · Physics 2009-10-30 D. M. Wei , T. Lu

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

Magnetars are modelled as sources that derive their output from magnetic energy that substantially exceeds their rotational energy. An implication of the recent polarization measurement of GRB 021206 is that the emission mechanism may be…

Astrophysics · Physics 2009-11-10 S. McBreen , L. Moran , B. McBreen , L. Hanlon , J. French , M. Conway

We consider the conditions within a Gamma-Ray Burst (GRB) emission region that is Poynting flux dominated. Due to the enormous magnetic energy density, relativistic electrons will cool in such a region extremely rapidly via synchrotron. As…

High Energy Astrophysical Phenomena · Physics 2015-06-18 Paz Beniamini , Tsvi Piran

We reexamine the general synchrotron model for GRBs' prompt emission and determine the regime in the parameter phase space in which it is viable. We characterize a typical GRB pulse in terms of its peak energy, peak flux and duration and…

High Energy Astrophysical Phenomena · Physics 2015-06-12 Paz Beniamini , Tsvi Piran

We propose a model in which prompt gamma emission of gamma-ray bursts is the synchrotron radiation of electron-positron plasma in the ordered magnetic field in the direct vicinity of horizon of a young black hole formed in the core collapse…

Astrophysics · Physics 2007-05-23 Andrey Neronov

Despite more than fifty years of gamma-ray burst (GRB) observations, several questions regarding the origin of the prompt emission, particularly at high energies, remain unresolved. We present a comprehensive analysis of 35 GRBs observed by…

High Energy Astrophysical Phenomena · Physics 2025-01-22 Samanta Macera , Biswajit Banerjee , Alessio Mei , Pawan Tiwari , Gor Oganesyan , Marica Branchesi

GRB afterglow polarization is discussed. We find an observable, up to 10%, polarization, if the magnetic field coherence length grows at about the speed of light after the field is generated at the shock front. Detection of a polarized…

Astrophysics · Physics 2011-03-17 Andrei Gruzinov , Eli Waxman

The energy dissipation mechanism within Gamma-Ray Burst (GRB) outflows, driving their extremely luminous prompt $\gamma$-ray emission is still uncertain. The leading candidates are internal shocks and magnetic reconnection. While the…

High Energy Astrophysical Phenomena · Physics 2016-05-13 Paz Beniamini , Jonathan Granot

Large-voltage and high-temperature plasma columns produced by pinch discharge can generate gamma-ray flashes with energy spectra and spectral evolution consistent with that observed in gamma-ray bursts (GRBs). The inverse Compton scattering…

Astrophysics · Physics 2014-10-13 Mei Wu , Li Chen , Ti-pei Li