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Title: Pitch angle scattering of relativistic electrons from stationary magnetic waves: Continuous Markov process and quasilinear theory

Abstract

We develop a Markov process theory of charged particle scattering from stationary, transverse, magnetic waves. We examine approximations that lead to quasilinear theory, in particular the resonant diffusion approximation. We find that, when appropriate, the resonant diffusion approximation simplifies the result of the weak turbulence approximation without significant further restricting the regime of applicability. We also explore a theory generated by expanding drift and diffusion rates in terms of a presumed small correlation time. This small correlation time expansion leads to results valid for relatively small pitch angle and large wave energy density - a regime that may govern pitch angle scattering of high-energy electrons into the geomagnetic loss cone.

Authors:
 [1]
  1. Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States)
Publication Date:
OSTI Identifier:
22043567
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physics of Plasmas; Journal Volume: 19; Journal Issue: 1; Other Information: (c) 2012 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
70 PLASMA PHYSICS AND FUSION TECHNOLOGY; APPROXIMATIONS; CHARGED PARTICLES; CORRELATIONS; DIFFUSION; ELECTRONS; ENERGY DENSITY; HYDROMAGNETIC WAVES; LOSS CONE; MARKOV PROCESS; PLASMA DIAGNOSTICS; PLASMA DRIFT; PLASMA SIMULATION; QUASILINEAR PROBLEMS; RELATIVISTIC PLASMA; RELATIVISTIC RANGE; SCATTERING; TURBULENCE

Citation Formats

Lemons, Don S. Pitch angle scattering of relativistic electrons from stationary magnetic waves: Continuous Markov process and quasilinear theory. United States: N. p., 2012. Web. doi:10.1063/1.3676156.
Lemons, Don S. Pitch angle scattering of relativistic electrons from stationary magnetic waves: Continuous Markov process and quasilinear theory. United States. doi:10.1063/1.3676156.
Lemons, Don S. 2012. "Pitch angle scattering of relativistic electrons from stationary magnetic waves: Continuous Markov process and quasilinear theory". United States. doi:10.1063/1.3676156.
@article{osti_22043567,
title = {Pitch angle scattering of relativistic electrons from stationary magnetic waves: Continuous Markov process and quasilinear theory},
author = {Lemons, Don S.},
abstractNote = {We develop a Markov process theory of charged particle scattering from stationary, transverse, magnetic waves. We examine approximations that lead to quasilinear theory, in particular the resonant diffusion approximation. We find that, when appropriate, the resonant diffusion approximation simplifies the result of the weak turbulence approximation without significant further restricting the regime of applicability. We also explore a theory generated by expanding drift and diffusion rates in terms of a presumed small correlation time. This small correlation time expansion leads to results valid for relatively small pitch angle and large wave energy density - a regime that may govern pitch angle scattering of high-energy electrons into the geomagnetic loss cone.},
doi = {10.1063/1.3676156},
journal = {Physics of Plasmas},
number = 1,
volume = 19,
place = {United States},
year = 2012,
month = 1
}
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