HR: 1340h
AN: SH33A-1198    [Abstracts]
TI: EXPLORING THE EVIDENCE OF PARTICLE-WAVE COUPLING IN THE DISTANT UPSTREAM ION-FORESHOCK
AU: * Fernandez Borda, R
EM: rfborda@lepvax.gsfc.nasa.gov
AF: Catholic University of America, 620 Michigan Ave., NE, Washington, DC 20064 United States
AU: Berdichevsky, D B
AF: L-3 Government Services, Inc, 1801McCormickDrive, Suite 170, Largo, MD 20774 United States
AU: Acuna, M H
EM: mha@lepmom.gsfc.nasa.gov
AF: NASA/Goddard Space Flight Center, Mail Stop 690, Greenbelt, MD 20771 United States
AU: Larson, D E
EM: davin@ssl.berkeley.edu
AF: University California Berkeley, Centenial Drv. at Grizzly Pk Bvd, BERKELEY, CA 94720 United States
AU: Lepping, R P
EM: rpl@leprpl1.gsfc.nasa.gov
AF: NASA/Goddard Space Flight Center, Mail Stop 690, Greenbelt, MD 20771 United States
AU: Maksimovic, M
EM: maksimovic@megasv.obspm.fr
AF: DESPA Observatoire de Meudon, Avenue du Chateau, Meudon-Cedex, 92195 France
AU: McEntire, R
EM: richard.mcentire@jhuapl.edu
AF: Johns Hopkins, APL, 11100 Johns Hopkins Rd., Laurel, MD 20723 United States
AU: Perche, C
EM: perche@obspm.fr
AF: DESPA Observatoire de Meudon, Avenue du Chateau, Meudon-Cedex, 92195 France
AU: Lin, R
EM: boblin@sunspot.ssl.berkeley.edu
AF: University California Berkeley, Centenial Drv. at Grizzly Pk Bvd, BERKELEY, CA 94720 United States
AU: Kasper, J
EM: jck@space.mit.edu
AF: MIT Space Science, 77 Mass. Ave.,, Cambridge, MA 02139 United States
AU: Nagai, T
EM: nagai@geo.titech.ac.jp
AF: Tokyo Institute of Technology, Earth and Planetary Sciences, Tokio, 152 8551 Japan
AB: We discuss the far ion foreshock for cases when the interplanetary magnetic field (IMF) is approximately parallel to the supersonic motion of the solar wind plasma. Several events have been identified of an enhanced ultra low frequency wave activity in the presence of an ion foreshock composed by (1) a beam (low energy <4keV), (2) a transverse population to the IMF ("intermediate" energy, from 5 to 40 keV), and (3) an isotropic population ("high" energy end, from 40 to 140 keV). This observations took place up to 250 RE upstream of the Earth (Berdichevsky et al., 1999¦). Here we study the frequency content, the polarization and the particle-wave coupling using a cross-spectrum analysis. We do a qualitative analysis of the origin of this wave-activity using the linear theory of plasma instabilities and explore the possibility of trapping of these strongly scattered particle fluxes. In this study we present results for observations on June 11, July 13, and Aug 25, 1995. For the study we use sampling times of waves and electron data of 12 sec or higher resolution energetic particle data. Solar wind plasma and magnetic field are collected by the MFI, SWE, WAVES, and 3DP instruments on Wind, and MGF and EPIC in GEOTAIL spacecraft. The spectral technique used is based on a set of Intrinsic Modes resulting from an Empirical Decomposition Method. Berdichevsky D. et al., 1999, J. Geophys. Res., 104, No A1, 463
DE: 7811 Discontinuities
DE: 2116 Energetic particles, planetary
DE: 2139 Interplanetary shocks
DE: 2149 MHD waves and turbulence
SC: SPA-Solar and Heliospheric Physics [SH]
MN: 2004 AGU Fall Meeting