HR: 11:45h
AN: SM52A-06    [Abstracts]
TI: Wave Particle Interactions of Velocity Dispersed Ion Structures
AU: * Ashour-Abdalla, M
EM: mabdalla@igpp.ucla.edu
AF: UCLA-IGPP, 405 Hilgard Avenue, Los Angeles, CA 90095-1567 United States
AU: * Ashour-Abdalla, M
EM: mabdalla@igpp.ucla.edu
AF: UCLA Department of Physics and Astronomy, 405 Hilgard Avenue, Los Angeles, CA 90095-1547 United States
AU: Leboeuf, J
EM: leboeuf@physics.ucla.edu
AF: UCLA Department of Physics and Astronomy, 405 Hilgard Avenue, Los Angeles, CA 90095-1547 United States
AU: Schriver, D
EM: dave@igpp.ucla.edu
AF: UCLA-IGPP, 405 Hilgard Avenue, Los Angeles, CA 90095-1567 United States
AU: Bosqued, J
EM: bosqued@cesr.fr
AF: Centre d'etude Spatiale des Rayonnements, 9 Avenue du Colonel-Roche, Toulouse, 31028 France
AU: Cornilleau-Werhlin, N
EM: nicole.cornilleau@cetp.ipsl.fr
AF: Centre d'etude des Environnements Terrestres et Planetaires, 10-12 Avenue de l'Europe, Velizy, 78140 France
AU: Sotnkov, V
EM: sotnikov@physics.unr.edu
AF: University of Nevada at Reno, Department of Physics, Reno, NV 89557 United States
AB: Cluster observations of the high latitude near-Earth plasma sheet show well defined velocity dispersed ion structures. They are associated with ion shell plasma distributions and are coincident with electrostatic and electromagnetic wave emissions. Shell distributions have a constant drift velocity in both the parallel and transverse directions, as opposed to a ring distribution, which has a drift only in the perpendicular direction. We have examined wave particle interactions that result from ion shell distributions like those observed by Cluster. We used a magnetized 2-1/2D electrostatic particle in cell (PIC) code with full ion dynamics for both the energetic shell and cold background, and guiding center electrons with full parallel dynamics. Results from the numerical simulations indicate that a combination of lower hybrid waves and ion Bernstein modes are excited accompanied by electron energy gain parallel to the ambient magnetic field as well as cold ion heating in both the parallel and transverse directions. The shell distribution tends to isotropize in velocity space due to the wave-particle interactions. We are in the process of examining electromagnetic emissions driven by the shell distribution using an electromagnetic PIC code and also will use observed distribution functions from Cluster to drive the simulations. Simulation results will be compared with relevant Cluster particle and wave observations
DE: 7827 Kinetic and MHD theory
DE: 7843 Numerical simulation studies
DE: 7867 Wave/particle interactions
SC: SPA-Magnetospheric Physics [SM]
MN: 2005 Joint Assembly