HR: 0830h
AN: SH51A-05    [Abstracts]
TI: Alfvenic Reconnection and Particle Energization in Solar-Terrestrial Plasmas
AU: * Song, Y
EM: yan@fields.space.umn.edu
AF: University of Minnesota, School of Physics and Astronomy 116 Church St. S.E. Tate Lab, Minneapolis, MN 55455 United States
AU: Lysak, R L
EM: bob@belka.space.umn.edu
AF: University of Minnesota, School of Physics and Astronomy 116 Church St. S.E. Tate Lab, Minneapolis, MN 55455 United States
AB: Magnetic reconnection and particle energization are two universal and important physical processes occurring in solar-terrestrial plasmas. The generation of electric fields, in particular, parallel electric fields, is a necessary condition for both processes. Most previous calculations of electric fields have been based on the generalized Ohm's Law. However, the generalized Ohm's law, which is essentially the electron momentum equation, only describes force balance, not the generation of the electric fields themselves. Magnetic reconnection often occurs when a pre-existing current sheet is compressed locally by external plasma forces. The parallel electric field responsible for breaking the frozen-in condition must be maintained long enough to provide for the observed particle energization during reconnection. Dynamical equations for the generation of electric fields during the compression of current sheets have been derived. These dynamical equations show that the generation of a sustained parallel electric field favors low plasma density. The continued presence of these electric fields requires a continuous energy supply by the release of localized magnetic or mechanical stresses. This implies that parallel electric field generation is a reactive process. While the basic dynamical equations for the generation of electric fields in current sheets are universal, the external stresses that drive these processes depend on the structure of the magnetic topology being considered. We will demonstrate how these stresses evolve in a number of important configurations, such as the Earth's magnetopause and geomagnetic tail, the auroral acceleration region, and in coronal loops.
DE: 2704 Auroral phenomena (2407)
DE: 2712 Electric fields (2411)
DE: 7807 Charged particle motion and acceleration
DE: 7835 Magnetic reconnection
SC: SPA-Solar and Heliospheric Physics [SH]
MN: 2005 Joint Assembly