HR: 0800h
AN: SM11A-0313    [Abstracts]
TI: The altered solar wind - magnetosphere coupling during low Mach number CMEs: Highlights from MHD simulations
AU: * Lavraud, B
EM: lavraud@lanl.gov
AF: Los Alamos National Laboratory, P.O. Box 1663, MS D466, Los Alamos, NM 87545, United States
AU: Borovsky, J E
EM: jborovsky@lanl.gov
AF: Los Alamos National Laboratory, P.O. Box 1663, MS D466, Los Alamos, NM 87545, United States
AB: In this paper we illustrate some expectations for the interaction between low Mach number solar wind (often characteristic of CMEs) and the magnetosphere. A result of the low (Alfven) Mach number solar wind is the formation of a low thermal beta magnetosheath downstream of the bow shock. Because of such properties, magnetic forces become prominent and largely rule the properties of the magnetosheath flow and of its coupling with the magnetosphere. We illustrate such effects by use of spacecraft data and MHD simulations for such a low-beta magnetosheath case. We generally predict (a) high-velocity flow jets in the magnetosheath adjacent to the magnetopause, (b) reduced flows in other regions of the magnetosheath, (c) asymmetric shapes for the magnetopause, (d) polar cap saturation and Alfven wings, and (d) anomalous magnetic field stretching of the dipolar portions of the magnetosphere, which we relate to the occurrence of sawtooth events. These effects have generally been overlooked and will deserve both small- and large-scale multi-spacecraft observations to be investigated.
DE: 2700 MAGNETOSPHERIC PHYSICS (6939)
DE: 2724 Magnetopause and boundary layers
DE: 2728 Magnetosheath
DE: 2740 Magnetospheric configuration and dynamics
DE: 2784 Solar wind/magnetosphere interactions
SC: SPA-Magnetospheric Physics [SM]
MN: 2007 Fall Meeting