HR: 0830h
AN: SM31B-1114    [PDF]
TI: Particle entry through sash in the magnetopause with a dawndard IMF as simulated by a 3-D EM particle code
AU: Cai, D
EM: cai@is.tsukuba.ac.jp
AF: The University of Tsukuba, Institute of Information Sciences and Electronics,, Tsukuba, Ibaraki, 305-8573 Japan
AU: Yan, X
EM: yxy@aoi3.is.tsukuba.ac.jp
AF: The University of Tsukuba, Institute of Information Sciences and Electronics,, Tsukuba, Ibaraki, 305-8573 Japan
AU: * Lembege, B
EM: Bertrand.Lembege@cetp.ipsl.fr
AF: CETP/UVSQ/IPSL, 10-12 Avenue de l'Europe, Velizy, FR-78140 France
AU: Nishikawa, K
EM: Ken-Ichi.Nishikawa@nsstc.nasa.gov
AF: National Space Science and Technology Center, 320 Sparkman Drive, SD 50, Huntsville, AL 35805 United States
AB: We report a new progress in the long-term effort to represent the global interaction of the solar wind with the Earth's magnetosphere using a three-dimensional electromagnetic particle code with the improved resolutions using the HPF Tristan code. After a quasi-steady state is established with an unmagnetized solar wind we gradually switch on a northward interplanetary magnetic field (IMF), which causes a magnetic reconnection at the nightside cusps and the magnetosphere to be depolarized. In the case that the northward IMF is switched gradually to dawnward, there is no signature of reconnection in the near-Earth magnetotail as in the case with the southward turning. On the contrary analysis of magnetic fields in the magnetopause confirms a signature of magnetic reconnection at both the dawnside and duskside. And the plasma sheet in the near-Earth magnetotail clearly thins as in the case of southward turning. Arrival of dawnward IMF to the magnetopause creates a reconnection groove which cause particle entry into the deep region of the magnetosphere via field lines that go near the magnetopause. This deep connection is more fully recognized tailward of Earth. The flank weak-field fan joins onto the plasma sheet and the current sheet to form a geometrical feature called the cross-tail S that structurally integrates the magnetopause and the tail interior. This structure contributes to direct plasma entry between the magnetosheath to the inner magnetosphere and plasma sheet, in which the entry process heats the magnetosheath plasma to plasma sheet temperatures. These phenomena have been found by Cluster observations. Further investigation with Cluster observations will provide new insights for unsolved problems such as hot flow anomalies (HFAs), substorms, and storm-substorm relationship. 3-D movies with sash structure will be presented at the meeting.
UR: http://gammaray.nsstc.nasa.gov/~nishikawa
DE: 2716 Energetic particles, precipitating
DE: 2724 Magnetopause, cusp, and boundary layers
DE: 2740 Magnetospheric configuration and dynamics
DE: 2753 Numerical modeling
DE: 2788 Storms and substorms
SC: SPA - Magnetospheric Physics [SM]
MN: 2003 Fall Meeting