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Title: Nonlinear electron acceleration by oblique whistler waves: Landau resonance vs. cyclotron resonance

Abstract

This paper is devoted to the study of the nonlinear interaction of relativistic electrons and high amplitude strongly oblique whistler waves in the Earth's radiation belts. We consider electron trapping into Landau and fundamental cyclotron resonances in a simplified model of dipolar magnetic field. Trapping into the Landau resonance corresponds to a decrease of electron equatorial pitch-angles, while trapping into the first cyclotron resonance increases electron equatorial pitch-angles. For 100 keV electrons, the energy gained due to trapping is similar for both resonances. For electrons with smaller energy, acceleration is more effective when considering the Landau resonance. Moreover, trapping into the Landau resonance is accessible for a wider range of initial pitch-angles and initial energies in comparison with the fundamental resonance. Thus, we can conclude that for intense and strongly oblique waves propagating in the quasi-electrostatic mode, the Landau resonance is generally more important than the fundamental one.

Authors:
; ;  [1];  [2];  [3]
  1. LPC2E/CNRS—University of Orleans, Orleans (France)
  2. Space Research Institute, RAS, Moscow (Russian Federation)
  3. CEA, DAM, DIF, Arpajon (France)
Publication Date:
OSTI Identifier:
22224185
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physics of Plasmas; Journal Volume: 20; Journal Issue: 12; Other Information: (c) 2013 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
70 PLASMA PHYSICS AND FUSION TECHNOLOGY; ACCELERATION; COMPARATIVE EVALUATIONS; ELECTRON CYCLOTRON-RESONANCE; ELECTRONS; GEOMAGNETIC FIELD; INCLINATION; KEV RANGE; MAGNETIC FIELDS; NONLINEAR PROBLEMS; RADIATION BELTS; RELATIVISTIC PLASMA; TRAPPING; WAVE PROPAGATION; WHISTLERS

Citation Formats

Artemyev, A. V., Agapitov, O. V., Krasnoselskikh, V. V., Vasiliev, A. A., and Mourenas, D. Nonlinear electron acceleration by oblique whistler waves: Landau resonance vs. cyclotron resonance. United States: N. p., 2013. Web. doi:10.1063/1.4836595.
Artemyev, A. V., Agapitov, O. V., Krasnoselskikh, V. V., Vasiliev, A. A., & Mourenas, D. Nonlinear electron acceleration by oblique whistler waves: Landau resonance vs. cyclotron resonance. United States. doi:10.1063/1.4836595.
Artemyev, A. V., Agapitov, O. V., Krasnoselskikh, V. V., Vasiliev, A. A., and Mourenas, D. 2013. "Nonlinear electron acceleration by oblique whistler waves: Landau resonance vs. cyclotron resonance". United States. doi:10.1063/1.4836595.
@article{osti_22224185,
title = {Nonlinear electron acceleration by oblique whistler waves: Landau resonance vs. cyclotron resonance},
author = {Artemyev, A. V. and Agapitov, O. V. and Krasnoselskikh, V. V. and Vasiliev, A. A. and Mourenas, D.},
abstractNote = {This paper is devoted to the study of the nonlinear interaction of relativistic electrons and high amplitude strongly oblique whistler waves in the Earth's radiation belts. We consider electron trapping into Landau and fundamental cyclotron resonances in a simplified model of dipolar magnetic field. Trapping into the Landau resonance corresponds to a decrease of electron equatorial pitch-angles, while trapping into the first cyclotron resonance increases electron equatorial pitch-angles. For 100 keV electrons, the energy gained due to trapping is similar for both resonances. For electrons with smaller energy, acceleration is more effective when considering the Landau resonance. Moreover, trapping into the Landau resonance is accessible for a wider range of initial pitch-angles and initial energies in comparison with the fundamental resonance. Thus, we can conclude that for intense and strongly oblique waves propagating in the quasi-electrostatic mode, the Landau resonance is generally more important than the fundamental one.},
doi = {10.1063/1.4836595},
journal = {Physics of Plasmas},
number = 12,
volume = 20,
place = {United States},
year = 2013,
month =
}
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