USP Electronic Research Repository

Effect of up-flowing field aligned electron beams on the electron cyclotron waves in the aural magnetosphere

Kumar, Sushil and Singh, Sunil K. and Gwal, A.K. (2007) Effect of up-flowing field aligned electron beams on the electron cyclotron waves in the aural magnetosphere. PRAMANA: Journal of Physics, 68 (4). pp. 611-615. ISSN 0304-4289

Full text not available from this repository.

Abstract

The role of low density up°owing ¯eld-aligned electron beams (FEBs) on the growth rate of the electron cyclotron waves at the frequencies !r < ­e, propagating downward in the direction of the Earth's magnetic ¯eld, has been analysed in the auroral region at !e=­e < 1 where !e is the plasma frequency and ­e is the gyrofrequency. The FEBs with low to high energy (Eb) but with low temperature (Tkb) have no e®ect on these waves. The FEBs with Eb < 1 keV and Tkb (>1.5 keV) have been found to have signi¯cant e®ect on the growth rate. Analysis has revealed that it is mainly the Tkb which inhibits the growth rate (magnitude) and the range of frequency (bandwidth) of the instability mainly in the higher frequency spectrum. The inhibition in the growth rate and bandwidth increases with increase in Tkb. The FEBs with less Eb (giving drift velocity) reduce growth rate more than the beams with larger Eb. The inhibition of growth rate increases with the increase in the ratio !e=­e indicating that the beams are more e®ective at higher altitudes.

Item Type: Journal Article
Subjects: Q Science > QC Physics
Divisions: Faculty of Science, Technology and Environment (FSTE) > School of Engineering and Physics
Depositing User: Ms Mereoni Camailakeba
Date Deposited: 26 Apr 2007 15:00
Last Modified: 11 Jul 2012 17:50
URI: http://repository.usp.ac.fj/id/eprint/4254
UNSPECIFIED

Actions (login required)

View Item