HR: 1340h
AN: SM33A-0427 [Abstracts]
TI: Whistler chorus intensifications associated with convections and injections of low energy plasma sheet
electrons evidenced by VELOX observations at Halley ground station
AU: * Hwang, J
EM: junga.hwang@gmail.com
AF: KAIST, Space Sciences Laboratory
Department of Physics, Korea Advanced Institute of Science and Technology, Daejeon, 305-701
Korea, Republic of
AU: Lee, D
EM: dylee@chungbuk.ac.kr
AF: Chungbuk National University, Dept. of Astronomy and Space Science, College of Natural Sciences and
Institute for Basic Science Research,
Chungbuk National University, Cheong-ju, 361-763
Korea, Republic of
AU: Lyons, L
EM: larry@atmos.ucla.edu
AF: UCLA, Department of Atmospheric Science, Unversity of California, Los Angeles, 90095-1565
United States
AU: Min, K
EM: kwmin@space.kaist.ac.kr
AF: KAIST, Space Sciences Laboratory
Department of Physics, Korea Advanced Institute of Science and Technology, Daejeon, 305-701
Korea, Republic of
AU: Smith, A
EM: a.j.smith@bas.ac.uk
AF: British Antarctic Survey, British Antarctic Survey, High Cross, Madingley Road, Cambridge, 30ET
United Kingdom
AB:
It has been suggested that the relativistic electron flux enhancements are caused by local electron energization resulting
from resonant interactions with enhanced whistler-mode chorus emissions that have been observed on the dawn side of the
magnetosphere. It has been also suggested that the whistler chorus may be enhanced by an interaction with the low energy
plasma sheet electrons. Recently, using ground-based chorus observations from the VELOX instrument at Halley station as an
indicator of magnetospheric chorus intensities, Lyons et al. [2005, JGR; Also to be present in this same session] have shown
for the high speed stream periods on November, 2003 that it is the periods of enhanced convection that precede substorm
expansions, and not the expansions themselves, that lead to the enhanced dawn-side chorus wave intensity. In the present
paper, we have extended their work by examining substantially more periods of high speed streams during 2003 and have found
that the conclusion by Lyons et al. generally holds true for any high speed stream periods that accompany the large amplitude
Alfven waves of the IMF. The Alfven waves consist of successive (every 2-3 hrs) northward turnings proceeded by moderate
southward periods that are responsible for the enhanced convection. Furthermore, using the same VELOX data, we have examined
the relation of storm time injections to the whistler chorus excitation. We report an ideal storm time interval that shows
the close association between the low energy injections, the whistler chorus intensification, and the relativistic electron
enhancement. We will discuss how the storm time continuous injections such as a sawtooth event are generally related to the
whistler chorus intensification.
DE: 2716 Energetic particles: precipitating
DE: 2720 Energetic particles: trapped
DE: 2774 Radiation belts
DE: 2788 Magnetic storms and substorms (7954)
DE: 2790 Substorms
SC: SPA-Magnetospheric Physics [SM]
MN: Fall Meeting 2005