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Plasma convection and ion beam generation in the plasma sheet boundary layer

Authors :
Moghaddam-Taaheri, E
Goertz, C. K
Smith, R. A
Source :
Journal of Geophysical Research. 96
Publication Year :
1991
Publisher :
United States: NASA Center for Aerospace Information (CASI), 1991.

Abstract

Because of the dawn-dusk electric field E(dd), plasma in the magnetotail convects from the lobe toward the central plasma sheet (CPS). In the absence of space or velocity diffusion due to plasma turbulence, convection would yield a steady state distribution function f = V exp (-2/3) g(v exp 2 V exp 2/3), where V is the flux tube volume. Starting with such a distribution function and a plasma beta which varies from beta greater than 1 in the CPS to beta much smaller than 1 in the lobe, the evolution of the ion distribution function was studied considering the combined effects of ion diffusion by kinetic Alfven waves (KAW) in the ULF frequency range (1-10 mHz) and convection due to E(dd) x B drift in the plasma sheet boundary layer (PSBL) and outer central plasma sheet (OCPS). The results show that, during the early stages after launching the KAWs, a beamlike ion distribution forms in the PSBL and at the same time the plasma density and temperature decrease in the OCPS. Following this stage, ions in the beams convect toward the CPS resulting in an increase of the plasma temperature in the OCPS.

Subjects

Subjects :
Geophysics

Details

Language :
English
ISSN :
01480227
Volume :
96
Database :
NASA Technical Reports
Journal :
Journal of Geophysical Research
Notes :
NAGW-970
Publication Type :
Report
Accession number :
edsnas.19910040943
Document Type :
Report