Please use this identifier to cite or link to this item: http://nopr.niscair.res.in/handle/123456789/8387
Title: Generation of kinetic Alfven wave by velocity shear in the plasma sheet boundary layer during substorm
Authors: Tiwari, B V
Mishra, Ruchi
Varma, P
Tiwari, M S
Keywords: Kinetic Alfven wave
Plasma sheet boundary layer
Substorm event
Weak and strong velocity shear
Landau damping
Loss of poynting flux
Issue Date: Dec-2006
Publisher: CSIR
Series/Report no.: H05H
Abstract: The kinetic Alfven wave (KAW) driven by velocity shear in the plasma sheet boundary layer (PSBL) has been investigated. Expressions for the dispersion relation and growth rate of the kinetic Alfven wave have been derived for the two regimes separately i.e., for the case of weak shear and strong shear. It is found that for both weak and strong shear regimes the resonant electrons act as the main energy source whereas; the ion longitudinal motion suppresses the instability in case of the strong shear. The results explain the generation of energetic KAWs in the PSBL during the substorm onset by the weak velocity shear. As the shear becomes strong during the substorm the energy of the KAWs is transferred to the plasma particles through the Landau damping of the wave, which may then lead to the parallel energisation of the electrons observed recently by Polar satellite. The loss of the Poynting flux, as observed by Polar and Akebono satellite, is also explained in terms of the Landau damping of the KAW by the strong shear of substorm. The temperature anisotropy and density of the plasma particles enhance the growth rate of shear driven KAW at the onset of the substorm.
Description: 917-926
URI: http://hdl.handle.net/123456789/8387
ISSN: 0975-1041 (Online); 0019-5596 (Print)
Appears in Collections:IJPAP Vol.44(12) [December 2006]

Files in This Item:
File Description SizeFormat 
IJPAP 44(12) 917-926.pdf307.2 kBAdobe PDFView/Open


Items in NOPR are protected by copyright, with all rights reserved, unless otherwise indicated.