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Title: Relativistic electron precipitation events driven by electromagnetic ion-cyclotron waves

Abstract

We adopt a canonical approach to describe the stochastic motion of relativistic belt electrons and their scattering into the loss cone by nonlinear EMIC waves. The estimated rate of scattering is sufficient to account for the rate and intensity of bursty electron precipitation. This interaction is shown to result in particle scattering into the loss cone, forming ∼10 s microbursts of precipitating electrons. These dynamics can account for the statistical correlations between processes of energization, pitch angle scattering, and relativistic electron precipitation events, that are manifested on large temporal scales of the order of the diffusion time ∼tens of minutes.

Authors:
;  [1]; ;  [2]
  1. NASA Goddard Space FlightCenter, Greenbelt, Maryland 20771 (United States)
  2. Department of Physics and Technology, Altai State University, Barnaul (Russian Federation)
Publication Date:
OSTI Identifier:
22303786
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physics of Plasmas; Journal Volume: 21; Journal Issue: 8; Other Information: (c) 2014 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; ELECTRON PRECIPITATION; INCLINATION; LOSS CONE; NONLINEAR PROBLEMS; RELATIVISTIC RANGE; SCATTERING

Citation Formats

Khazanov, G., E-mail: george.v.khazanov@nasa.gov, Sibeck, D., Tel'nikhin, A., and Kronberg, T.. Relativistic electron precipitation events driven by electromagnetic ion-cyclotron waves. United States: N. p., 2014. Web. doi:10.1063/1.4892185.
Khazanov, G., E-mail: george.v.khazanov@nasa.gov, Sibeck, D., Tel'nikhin, A., & Kronberg, T.. Relativistic electron precipitation events driven by electromagnetic ion-cyclotron waves. United States. doi:10.1063/1.4892185.
Khazanov, G., E-mail: george.v.khazanov@nasa.gov, Sibeck, D., Tel'nikhin, A., and Kronberg, T.. Fri . "Relativistic electron precipitation events driven by electromagnetic ion-cyclotron waves". United States. doi:10.1063/1.4892185.
@article{osti_22303786,
title = {Relativistic electron precipitation events driven by electromagnetic ion-cyclotron waves},
author = {Khazanov, G., E-mail: george.v.khazanov@nasa.gov and Sibeck, D. and Tel'nikhin, A. and Kronberg, T.},
abstractNote = {We adopt a canonical approach to describe the stochastic motion of relativistic belt electrons and their scattering into the loss cone by nonlinear EMIC waves. The estimated rate of scattering is sufficient to account for the rate and intensity of bursty electron precipitation. This interaction is shown to result in particle scattering into the loss cone, forming ∼10 s microbursts of precipitating electrons. These dynamics can account for the statistical correlations between processes of energization, pitch angle scattering, and relativistic electron precipitation events, that are manifested on large temporal scales of the order of the diffusion time ∼tens of minutes.},
doi = {10.1063/1.4892185},
journal = {Physics of Plasmas},
number = 8,
volume = 21,
place = {United States},
year = {Fri Aug 15 00:00:00 EDT 2014},
month = {Fri Aug 15 00:00:00 EDT 2014}
}
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  • Relativistic electrons have been thought to more easily resonate with electromagnetic ion cyclotron EMIC waves if the total density is large. We show that, for a particular EMIC mode, this dependence is weak due to the dependence of the wave frequency and wave vector on the density. A significant increase in relativistic electron minimum resonant energy might occur for the H band EMIC mode only for small density, but no changes in parameters significantly decrease the minimum resonant energy from a nominal value. The minimum resonant energy depends most strongly on the thermal velocity associated with the field line motionmore » of the hot ring current protons that drive the instability. High density due to a plasmasphere or plasmaspheric plume could possibly lead to lower minimum resonance energy by causing the He band EMIC mode to be dominant. We demonstrate these points using parameters from a ring current simulation.« less
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