Relativistic electron scattering by magnetosonic waves: Effects of discrete wave emission and high wave amplitudes

TitleRelativistic electron scattering by magnetosonic waves: Effects of discrete wave emission and high wave amplitudes
Publication TypeJournal Article
Year of Publication2015
AuthorsArtemyev, AV, Mourenas, D, Agapitov, OV, Krasnoselskikh, VV
JournalPhysics of Plasmas
Volume22
Issue6
Pagination062901
Date Published06/2015
ISSN1070-664X
Keywordschorus waves; CLUSTER SPACECRAFT; equatorial noise; MAGNETIC-FIELD; PLASMA; QUASI-LINEAR DIFFUSION; radiation belt electrons; RESONANT SCATTERING; Van Allen Probes; WHISTLER-MODE WAVES
AbstractIn this paper, we study relativistic electron scattering by fast magnetosonic waves. We compare results of test particle simulations and the quasi-linear theory for different spectra of waves to investigate how a fine structure of the wave emission can influence electron resonant scattering. We show that for a realistically wide distribution of wave normal angles theta (i.e., when the dispersion delta theta >= 0.5 degrees), relativistic electron scattering is similar for a wide wave spectrum and for a spectrum consisting in well-separated ion cyclotron harmonics. Comparisons of test particle simulations with quasi-linear theory show that for delta theta > 0.5 degrees, the quasi-linear approximation describes resonant scattering correctly for a large enough plasma frequency. For a very narrow h distribution (when delta theta >= 0.05 degrees), however, the effect of a fine structure in the wave spectrum becomes important. In this case, quasi-linear theory clearly fails in describing accurately electron scattering by fast magnetosonic waves. We also study the effect of high wave amplitudes on relativistic electron scattering. For typical conditions in the earth's radiation belts, the quasi-linear approximation cannot accurately describe electron scattering for waves with averaged amplitudes > 300 pT. We discuss various applications of the obtained results for modeling electron dynamics in the radiation belts and in the Earth's magnetotail. (C) 2015 AIP Publishing LLC.
URLhttp://scitation.aip.org/content/aip/journal/pop/22/6/10.1063/1.4922061
DOI10.1063/1.4922061
Short TitlePhys. Plasmas


Page Last Modified: August 6, 2015