HR: 11:20h
AN: SH12B-05    [Abstracts]
TI: Hybrid simulations of the interaction of a current sheet with the termination shock
AU: * Giacalone, J
EM: giacalon@lpl.arizona.edu
AF: Department of Planetary Sciences, University of Arizona, 1629 E University, Tucson, AZ 85721, United States
AU: Burgess, D
EM: D.Burgess@qmul.ac.uk
AF: Astronomy Unit, Queen Mary, University of London, Mile End Road, London, E1 4NS, United Kingdom
AB: We address the physics of the interaction of a current sheet with the solar-wind termination shock by utilizing self- consistent hybrid simulations. The characteristics of the region near the shock and the intersection point with a current sheet depends largely on the orientation of the field. For example, if the magnetic field changes sign across the current sheet in such a way that the drift of charged particles is directed away from the shock, a large region of hot, low density plasma, known as a hot-flow anomaly forms near the shock. This may be relevant to our understanding of observations made by the Voyager spacecraft near the termination shock. Voyager 1 observed a heliospheric current sheet sector boundary just prior to its crossing of the shock. We find from our simulations that the size of this region is at least a few million km in diameter; thus, it could take several hours for a Voyager spacecraft to cross through this region and observe its characteristics. In addition, the interaction of current sheets with shocks leads to, among other things, efficient particle acceleration, and turbulent downstream plasmas which may be relevant to Voyager observations of the heliosheath. Our new numerical simulations address the formation of these regions, their spatial sizes, and how they are influenced by large-scale upstream turbulence, which exists in the regions between current sheets. We also examine the influence on various ionic species. Implications for spacecraft observations will be discussed.
DE: 2114 Energetic particles (7514)
DE: 2124 Heliopause and solar wind termination
DE: 7811 Discontinuities (2109)
DE: 7851 Shock waves (4455)
SC: SPA-Solar and Heliospheric Physics [SH]
MN: 2007 Fall Meeting