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Title: Origin of Intense Electron Heating in Relativistic Blast Waves
Abstract The modeling of gamma-ray burst afterglow emission bears witness to strong electron heating in the precursor of Weibel-mediated, relativistic collisionless shock waves propagating in unmagnetized electron–ion plasmas. In this Letter, we propose a theoretical model, which describes electron heating via a Joule-like process caused by pitch-angle scattering in the decelerating, self-induced microturbulence and the coherent charge-separation field induced by the difference in inertia between electrons and ions. The emergence of this electric field across the precursor of electron–ion shocks is confirmed by large-scale particle-in-cell (PIC) simulations. Integrating the model using a Monte Carlo-Poisson method, we compare the main observables to the PIC simulations to conclude that the above mechanism can indeed account for the bulk of electron heating.  more » « less
Award ID(s):
1804048
PAR ID:
10402210
Author(s) / Creator(s):
; ;
Date Published:
Journal Name:
The Astrophysical Journal Letters
Volume:
930
Issue:
1
ISSN:
2041-8205
Page Range / eLocation ID:
L8
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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