HR: 1400h
AN: SM53A-09    [Abstracts]
TI: Sources and sinks of equatorially mirroring protons and electrons within the nightside magnetosphere
AU: * Klida, M M
EM: mklida@bu.edu
AF: Center for Space Physics, Boston University, 725 Commonwealth Avenue, Boston, MA 02215, United States
AU: Fritz, T A
EM: fritz@bu.edu
AF: Center for Space Physics, Boston University, 725 Commonwealth Avenue, Boston, MA 02215, United States
AB: The Imaging Electron Spectrometer (IES) and Imaging Proton Spectrometer (IPS) on the Polar satellite have frequently measured temporary deviations in the isotropy of the pitch angle distributions (PADs) in the nightside region of the magnetosphere inside of 10 R_E. Depressions in the observed fluxes of electrons occur with pitch angles around 90° in the equatorial zone, while the more field aligned electrons remain largely unchanged. These butterfly distributions are a regular feature of the equatorial magnetosphere. The orbital precessions of Polar have allowed much of the inner magnetosphere to be observed, approximately 2 ~ 10 _E. Electron and proton paths of motion are simulated varied pitch angles for a specific event on 26 October 1999. In addition to a normal butterfly PAD on this day, Polar also observes a short, but intense localized injection of 90° pitch angle ions. The modeling effort can suggest that the magnetopause can play a significant role in both the loss and injection of equatorially drifting particles within the outer regions of the inner magnetosphere.
DE: 2716 Energetic particles: precipitating
DE: 2720 Energetic particles: trapped
DE: 2724 Magnetopause and boundary layers
DE: 2753 Numerical modeling
SC: SPA-Magnetospheric Physics [SM]
MN: 2007 Joint Assembly