HR: 0800h
AN: SM21A-0301    [Abstracts]
TI: Estimations of the convection electric field from plasmaspheric images and geostationary energetic particle measurements; direct comparison
AU: * Larsen, B A
EM: balarsen@bu.edu
AF: Center for Space Physics Boston University, 725 Commonwealth Ave Rm 506, Boston, MA 01125, United States
AB: Global scale electric fields control the dynamics of low energy plasma in the inner magnetosphere. Through the study of plasmaspheric images from the IMAGE EUV instrument it is possible to estimate the zero energy Alfven layer by tracking convection and corotation motion of bulk plasmaspheric plasma. From the zero energy Alfven layer the convection electric field is derived based on a Volland-Stern field pattern. This work presents these observations, as well as a comparison with an estimation method based on LANL geostationary observations of the plasma sheet electron cutoff energy. Co-temporal observations agree in terms of electric field strength using both techniques. However, the EUV images add another dimension to the derivation, providing additional information that can be used to enhance the determination of electric field structure. This combination of techniques determines the electric field structure more completely. Based on this structure the dynamics of much of the inner magentosphere can be approached, such as the overlap of the plasmasphere/plasmapause and the drift paths of radiation belt particles, as well as the interactions made possible by this overlap.
DE: 2712 Electric fields (2411)
DE: 2730 Magnetosphere: inner
DE: 2760 Plasma convection (2463)
DE: 2768 Plasmasphere
SC: SPA-Magnetospheric Physics [SM]
MN: 2007 Fall Meeting