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Title: High‐Frequency Wave Generation in Magnetotail Reconnection: Nonlinear Harmonics of Upper Hybrid Waves
Abstract

MMS3 spacecraft passed the vicinity of the electron diffusion region of magnetotail reconnection on 3 July 2017, observing discrepancies between perpendicular electron bulk velocities anddrift, and agyrotropic electron crescent distributions. Analyzing linear wave dispersions, Burch et al. (2019,https://doi.org/10.1029/2019GL082471) showed the electron crescent generates high‐frequency waves. We investigate harmonics of upper‐hybrid (UH) waves using both observation and particle‐in‐cell (PIC) simulation, and the generation of electromagnetic radiation from PIC simulation. Harmonics of UH are linearly polarized and propagate along the perpendicular direction to the ambient magnetic field. Compared with two‐dimensional PIC simulation and nonlinear kinetic theory, we show that the nonlinear beam‐plasma interaction between the agyrotropic electrons and the core electrons generates harmonics of UH. Moreover, PIC simulation shows that agyrotropic electron beam can lead to electromagnetic (EM) radiation at the plasma frequency and harmonics.

 
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NSF-PAR ID:
10374353
Author(s) / Creator(s):
 ;  ;  ;  ;  ;  ;  
Publisher / Repository:
DOI PREFIX: 10.1029
Date Published:
Journal Name:
Geophysical Research Letters
Volume:
46
Issue:
14
ISSN:
0094-8276
Page Range / eLocation ID:
p. 7873-7882
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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