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Related papers: Linear and circular polarization in GRB afterglows

200 papers

Following a BeppoSAX alert (Piro 1999a) and the discovery of the OT at SAAO (Vreeswijk et al. 1999a), we observed GRB 990510 with the FORS instrument on ESO's VLT Unit 1 (`Antu'). The burst is unremarkable in gamma rays, but in optical is…

A relativistic electron-positron beam propagating through a magnetized electron-ion plasma is shown to generate both circularly and linearly polarized synchrotron radiation. The degrees of circular and linear polarizations depend both on…

Plasma Physics · Physics 2019-05-29 Ujjwal Sinha , Christoph H. Keitel , Naveen Kumar

The detection of an afterglow, following a gamma-ray burst (GRB), can be described reasonably well by synchrotron emission from a relativistic spherical expanding blast wave, driven by an expanding fireball. We perform detailed calculations…

Astrophysics · Physics 2011-03-17 Jonathan Granot , Tsvi Piran , Re'em Sari

The X-ray afterglow plateau emission observed in many Gamma-ray Bursts (GRBs) has been interpreted as either being fueled by fallback onto a newly formed black hole, or by the spin-down luminosity of an ultra-magnetized millisecond neutron…

High Energy Astrophysical Phenomena · Physics 2018-12-26 G. Stratta , M. G. Dainotti , S. Dall'Osso , X. Hernandez , G. De Cesare

Synchrotron is considered the dominant emission mechanism in the production of gamma-ray burst photons in the prompt as well as in the afterglow phase. Polarization is a characteristic feature of synchrotron and its study can reveal a…

Astrophysics · Physics 2009-11-11 Davide Lazzati

The dominant radiation mechanism that produces the prompt emission in gamma-ray bursts (GRBs) remains a major open question. Spectral information alone has proven insufficient in elucidating its nature. Time-resolved linear polarization has…

High Energy Astrophysical Phenomena · Physics 2021-04-21 Ramandeep Gill , Jonathan Granot

Gamma-Ray Burst afterglow polarization measurements, in spite of their intrinsic difficulties, have been carried out for a number of events that begins to be adequate to draw some general statistical conclusions. Although the presence of…

Astrophysics · Physics 2008-11-26 Stefano Covino , Gabriele Ghisellini , Davide Lazzati , Daniele Malesani

We show that isotropic component of circular polarization of stochastic gravitational wave background can be explored by breaking two dimensional configuration of multiple laser interferometers for correlation analysis. By appropriately…

Astrophysics · Physics 2008-11-26 Naoki Seto

We present polarimetric observations of the afterglow of gamma-ray burst (GRB) 021004, obtained with the Nordic Optical Telescope (NOT) and the Very Large Telescope (VLT) between 8 and 17 hours after the burst. Comparison among the…

Polarization measurements of the prompt emission in Gamma-ray Bursts (GRBs) can provide diagnostic information for understanding the nature of the central engine. POLAR is a compact polarimeter dedicated to the polarization measurement of…

Instrumentation and Methods for Astrophysics · Physics 2015-05-13 Shaolin Xiong , Nicolas Produit , Bobing Wu

For gravitational wave (GW) detected neutron star mergers, one of the leading candidates for electromagnetic (EM) counterparts is the afterglow from an ultra-relativistic jet. Where this afterglow is observed, it will likely be viewed…

High Energy Astrophysical Phenomena · Physics 2021-09-02 Gavin P Lamb , Joseph J Fernández , Fergus Hayes , Albert K H Kong , En-Tzu Lin , Nial R Tanvir , Martin Hendry , Ik Siong Heng , Surojit Saha , John Veitch

Radio observations of gamma-ray burst (GRB) afterglows are essential for our understanding of the physics of relativistic blast waves, as they enable us to follow the evolution of GRB explosions much longer than the afterglows in any other…

We report the detection of linear polarization from SgrA* at 750, 850, 1350 and 2000 microns which confirms the contribution of synchrotron radiation. From the lack of polarization at longer wavelengths it appears to arise in the…

Radio observations of gamma-ray burst (GRB) afterglows are essential for our understanding of the physics of relativistic blast waves, as they enable us to follow the evolution of GRB explosions much longer than the afterglows in any other…

The polarization curve of GRB 020813 is discussed and compared to different models for the structure, evolution and magnetisation properties of the jet and the interstellar medium onto which the fireball impacts. GRB 020813 is best suited…

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 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

Gamma-Ray Burst (GRB) afterglows are commonly interpreted as synchrotron emission from a relativistic blast wave produced by a point explosion in an ambient medium, plausibly the interstellar medium of galaxies. We calculate the amplitude…

Astrophysics · Physics 2009-10-31 Xiaohu Wang , Abraham Loeb

Recent detections of gamma-ray bursts (GRBs) at TeV energies opened new prospects for investigating radiative environments and particle acceleration mechanisms under extreme conditions. In this paper, we study the afterglows of these GRBs -…

High Energy Astrophysical Phenomena · Physics 2025-11-27 L. Foffano , M. Tavani

X-ray flares, lasting for $\sim 100 - 1000$ s in the X-ray band, are often observed following gamma-ray bursts (GRBs). The physical origin of X-ray flares is still unknown merely with the temporal/spectral information. On the other hand,…

High Energy Astrophysical Phenomena · Physics 2018-08-08 Jin-Jun Geng , Yong-Feng Huang , Xue-Feng Wu , Li-Ming Song , Hong-Shi Zong