HR: 13:40h
AN: SH53B-01 INVITED     [Abstracts]
TI: An Overview of Ion Distributions Upstream from the Earth Bow Shock
AU: * Scholer, M
EM: scholer@mpe.mpg.de
AF: Max-Planck-Inst. extraterr. Physik, P.O. Box 1312, Garching, 85741 Germany
AB: A variety of suprathermal and energetic ion distrbutions are found upstream of Earth's bow shock. The distributions can be broadly divided into specularly reflected ions, field-aligned beams, intermediate ions, and diffuse ions. In addition gyrophase bunched and more gyrotropic ring-beam distributions have been observed in certain foreshock regions. We will first review these observations and then critically discuss the current understanding of the creation and evolution of the suprathermal distributions at shocks. Processes include specular reflection, shock drift acceleration, multiple interactions with the shock during reflection, phase trapping of beam distributions, and diffusive acceleration. We will also discuss the processes which have been proposed for injection of solar wind ions into diffusive shock acceleration. Finally, we will point out open problems and suggest directions for future research.
DE: 2114 Energetic particles (7514)
DE: 2154 Planetary bow shocks
DE: 7807 Charged particle motion and acceleration
DE: 7851 Shock waves (4455)
SC: SPA-Solar and Heliospheric Physics [SH]
MN: Fall Meeting 2005