HR: 08:30h
AN: SM41A-03 [Abstracts]
TI: Generation and propagation of Pc1-2 waves in the magnetosphere: Effects of heavy ions
AU: Lee, D
EM: dhlee@khu.ac.kr
AF: Kyung Hee University, Department of Astronomy and Space Science, Yongin, 449-701,
Korea, Republic of
AU: Kim, K
AF: Kyung Hee University, Department of Astronomy and Space Science, Yongin, 449-701,
Korea, Republic of
AU: Kim, K
AF: Ajou University, Division of Energy Systems Research, Sowon, 442-749, Korea, Republic of
AU: * Johnson, J R
EM: jrj@pppl.gov
AF: Princeton University, Plasma Physics Laboratory, Princeton, NJ 08543, United States
AU: Kim, E
AF: University of Sydney, School of Physics, New South Wales, 2006, Australia
AB:
Previous statistical studies show that Pc1-2 waves are found frequently with linear polarization
near the equatorial region. Since the dispersion relation indicates that the polarization of most Pc1-2 wave events
should be either left-handed or right-handed, it has remained as a long-standing, unanswered question.
Our study suggests that these linearly-polarized events are generated by mode conversion of
compressional waves into heavy ion resonances, called Buchsbaum-Bers and ion-ion hybrid resonances, which
correspond to Alfven resonances in the low frequency limit.
We examine how these resonances occur for various heavy ion population and source sizes in detail
by performing an accurate calculation on the mode conversion efficiency. The dependence of the efficiency on the
relative abundance among different ions is investigated and found to be consistent with observational features.
From tha fact that the Buchsbaum-Bers resonance frequency is determined only by the magnetic field and relative
population
density of heavy ions, we suggest that monitoring the local heavy ion population is possible simply
by examining peak frequencies of the linearly polarized wave events.
DE: 2752 MHD waves and instabilities (2149, 6050, 7836)
DE: 2772 Plasma waves and instabilities (2471)
DE: 7827 Kinetic and MHD theory
DE: 7867 Wave/particle interactions (2483, 6984)
SC: SPA-Magnetospheric Physics [SM]
MN: 2007 Joint Assembly