HR: 14:10h
AN: SM23D-03    [Abstracts]
TI: Global hybrid simulations: ULF waves in the magnetosheath
AU: * Blanco-Cano, X
EM: xbc@geofisica.unam.mx
AF: Instituto de Geofisica, Universidad Nacional Autonoma de Mexico, Ciudad Universitaria, Coyoacan, Mexico, DF 94510, Mexico
AU: Omidi, N
EM: omidi@adelphia.net
AF: Solana Scientific Inc., 777 S. HWY 101, suite 208B, Solana Beach, CA 92075, United States
AU: Russell, C
EM: ctrussel@igpp.ucla.edu
AF: IGPP, University of California, 405 Hilgard Av., Los Angeles, CA 90095, United States
AB: Solar wind interaction with Earth's magnetosphere has been found to be more complex than originally thought. This complexity arises because the interaction region is dominated by kinetic effects that affect the large-scale dynamics of the sub-regions that form, namely the foreshock, bow shock and magnetosheath. In this work we use global hybrid simulations to study solar wind coupling with the magnetosphere for oblique (45°) and radial IMF geometries. Global hybrid simulations give a collective picture of processes taking place in the foreshock, bow shock and magnetosheath. Because ions are treated as particles, these codes also give information on ion-scale microphysics allowing us to understand how kinetic phenomena modulate global characteristics. We concentrate on the origin and characteristics of low frequency waves in the magnetosheath. This region is extremely inhomogeneous characterized by a variety of waves, which result from the convection of upstream waves, modes generated at the shock and also from local instabilities. When the IMF is oblique, our simulations show the existence of mirror mode and ion cyclotron waves. We study ion association with the waves to determine instability thresholds. For a radial IMF geometry large structures with density and magnetic field anticorrelated form in the dayside magnetosheath.
DE: 2159 Plasma waves and turbulence
DE: 2728 Magnetosheath
DE: 2772 Plasma waves and instabilities (2471)
SC: SPA-Magnetospheric Physics [SM]
MN: 2007 Fall Meeting