Time-varying Polarized Gamma-Rays from GRB 160821A: Evidence for Ordered Magnetic Fields

Vidushi Sharma; Shabnam Iyyani; Dipankar Bhattacharya; Tanmoy Chattopadhyay; A. R. Rao; E. Aarthy; Santosh V. Vadawale; N. P.S. Mithun; Varun B. Bhalerao; Felix Ryde; Asaf Pe'Er

doi:10.3847/2041-8213/ab3a48

Time-varying Polarized Gamma-Rays from GRB 160821A: Evidence for Ordered Magnetic Fields

Vidushi Sharma, Shabnam Iyyani, Dipankar Bhattacharya, Tanmoy Chattopadhyay, A. R. Rao, E. Aarthy, Santosh V. Vadawale, N. P.S. Mithun, Varun B. Bhalerao, Felix Ryde, Asaf Pe'Er

Department of Physics - at Bar-Ilan University

Bar-Ilan University

Research output: Contribution to journal › Article › peer-review

Abstract

GRB 160821A is the third most energetic gamma-ray burst observed by the Fermi gamma-ray space telescope. Based on the observations made by the Cadmium Zinc Telluride Imager on board AstroSat, here we report the most conclusive evidence to date of (i) high linear polarization ( detection), and (ii) variation of polarization angle with time, occurring twice during the rise and decay phase of the burst at 3.5σ and 3.1σ detections, respectively. All confidence levels are reported for two parameters of interest. These observations strongly suggest synchrotron radiation produced in magnetic field lines that are highly ordered on angular scales of 1/Γ, where Γ is the Lorentz factor of the outflow.

Original language	English
Article number	L10
Journal	Astrophysical Journal Letters
Volume	882
Issue number	1
DOIs	https://doi.org/10.3847/2041-8213/ab3a48
State	Published - 1 Sep 2019

All Science Journal Classification (ASJC) codes

Astronomy and Astrophysics
Space and Planetary Science

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title = "Time-varying Polarized Gamma-Rays from GRB 160821A: Evidence for Ordered Magnetic Fields",

abstract = "GRB 160821A is the third most energetic gamma-ray burst observed by the Fermi gamma-ray space telescope. Based on the observations made by the Cadmium Zinc Telluride Imager on board AstroSat, here we report the most conclusive evidence to date of (i) high linear polarization ( detection), and (ii) variation of polarization angle with time, occurring twice during the rise and decay phase of the burst at 3.5σ and 3.1σ detections, respectively. All confidence levels are reported for two parameters of interest. These observations strongly suggest synchrotron radiation produced in magnetic field lines that are highly ordered on angular scales of 1/Γ, where Γ is the Lorentz factor of the outflow.",

author = "Vidushi Sharma and Shabnam Iyyani and Dipankar Bhattacharya and Tanmoy Chattopadhyay and Rao, \{A. R.\} and E. Aarthy and Vadawale, \{Santosh V.\} and Mithun, \{N. P.S.\} and Bhalerao, \{Varun B.\} and Felix Ryde and Asaf Pe'Er",

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doi = "10.3847/2041-8213/ab3a48",

language = "الإنجليزيّة",

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TY - JOUR

T1 - Time-varying Polarized Gamma-Rays from GRB 160821A

T2 - Evidence for Ordered Magnetic Fields

AU - Sharma, Vidushi

AU - Iyyani, Shabnam

AU - Bhattacharya, Dipankar

AU - Chattopadhyay, Tanmoy

AU - Rao, A. R.

AU - Aarthy, E.

AU - Vadawale, Santosh V.

AU - Mithun, N. P.S.

AU - Bhalerao, Varun B.

AU - Ryde, Felix

AU - Pe'Er, Asaf

PY - 2019/9/1

Y1 - 2019/9/1

N2 - GRB 160821A is the third most energetic gamma-ray burst observed by the Fermi gamma-ray space telescope. Based on the observations made by the Cadmium Zinc Telluride Imager on board AstroSat, here we report the most conclusive evidence to date of (i) high linear polarization ( detection), and (ii) variation of polarization angle with time, occurring twice during the rise and decay phase of the burst at 3.5σ and 3.1σ detections, respectively. All confidence levels are reported for two parameters of interest. These observations strongly suggest synchrotron radiation produced in magnetic field lines that are highly ordered on angular scales of 1/Γ, where Γ is the Lorentz factor of the outflow.

AB - GRB 160821A is the third most energetic gamma-ray burst observed by the Fermi gamma-ray space telescope. Based on the observations made by the Cadmium Zinc Telluride Imager on board AstroSat, here we report the most conclusive evidence to date of (i) high linear polarization ( detection), and (ii) variation of polarization angle with time, occurring twice during the rise and decay phase of the burst at 3.5σ and 3.1σ detections, respectively. All confidence levels are reported for two parameters of interest. These observations strongly suggest synchrotron radiation produced in magnetic field lines that are highly ordered on angular scales of 1/Γ, where Γ is the Lorentz factor of the outflow.

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DO - 10.3847/2041-8213/ab3a48

M3 - مقالة

SN - 2041-8205

VL - 882

JO - Astrophysical Journal Letters

JF - Astrophysical Journal Letters

IS - 1

M1 - L10

ER -

Time-varying Polarized Gamma-Rays from GRB 160821A: Evidence for Ordered Magnetic Fields

Abstract

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