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Title: Kinetic simulations of the filamentation instability in pair plasmas
ABSTRACT

The non-linear interaction between electromagnetic waves and plasmas attracts significant attention in astrophysics because it can affect the propagation of Fast Radio Bursts (FRBs) – luminous millisecond-duration pulses detected at radio frequency. The filamentation instability (FI) – a type of non-linear wave–plasma interaction – is considered to be dominant near FRB sources, and its non-linear development may also affect the inferred dispersion measure of FRBs. In this paper, we carry out fully kinetic particle-in-cell simulations of the FI in unmagnetized pair plasmas. Our simulations show that the FI generates transverse density filaments, and that the electromagnetic wave propagates in near vacuum between them, as in a waveguide. The density filaments keep merging until force balance between the wave ponderomotive force and the plasma pressure gradient is established. We estimate the merging time-scale and discuss the implications of filament merging for FRB observations.

 
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Award ID(s):
2206607
NSF-PAR ID:
10408949
Author(s) / Creator(s):
; ;
Publisher / Repository:
Oxford University Press
Date Published:
Journal Name:
Monthly Notices of the Royal Astronomical Society
Volume:
522
Issue:
2
ISSN:
0035-8711
Page Range / eLocation ID:
p. 2133-2144
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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