HR: 1330h
AN: SM12A-1197    [PDF]
TI: Cusp Region as Viewed by Energetic Electrons and Ions:A Statistical Study Using Cluster Rapid Data
AU: * Zhang, H
EM: zhang@bu.edu
AF: Center for Space Physics,Boston University, Center for Space Physics,BU 725 Commonwealth Ave., Boston, MA 02215
AU: Fritz, T
EM: fritz@bu.edu
AF: Center for Space Physics,Boston University, Center for Space Physics,BU 725 Commonwealth Ave., Boston, MA 02215
AU: Zong, Q
EM: zong@bu.edu
AF: Center for Space Physics,Boston University, Center for Space Physics,BU 725 Commonwealth Ave., Boston, MA 02215
AU: Daly, P
EM: daly@linpi.mpg.de
AF: Max-Plank-Institut,Germany, Max-Plank-Institut fur D-37191,Katlenburg-Lindau,Germany, Lindau, D-37191
AB: We present statistical results from the energetic electron and ion data set obtained by the RAPID experiment on Cluster when these satellites were in the vicinity of the dayside cusp and magnetopause.The energy range of RAPID for ions extends from 30 to 1500 keV and for electrons from 20 to 400 keV.The data used were obtained from Jan.1 to Apr.30, 2001 and Mar.1 to Apr.30,2002 to identify the cusp, to study its longitudinal extent in magnetic local time, to study its dependence on the solar wind velocity and the Interplanetary Magnetic Field(IMF) and to determine the relationship of energetic particles to this region. Furthermore, the relation between the energetic particles and local plasma and magnetic field is explored in detail for two events. The criteria used to identify the cusp region are: 1. High density(comparable to that in the sheath) 2. Small or stagnant plasma flow( $<$ 60 km/s ) 3. Turbulent magnetic field Energetic ions are essentially present on each pass (~80% of such opportunities)through this region.The energetic electron behavior observed in the cusp region was significantly more structured and variable than the ions. The location of cusp is affected by IMF By and/or solar wind Vy( solar wind dynamic pressure on Y-direction). The particle spectra are characterized by a power law and the power law index is found to be closely related to solar wind velocity.
DE: 2700 MAGNETOSPHERIC PHYSICS
DE: 2720 Energetic particles, trapped
DE: 2724 Magnetopause, cusp, and boundary layers
DE: 2728 Magnetosheath
DE: 2731 Magnetosphere--outer
SC: SPA - Magnetospheric Physics [SM]
MN: 2003 Fall Meeting