HR: 0800h
AN: SM31D-0664    [Abstracts]
TI: A GKE/FKI Particle Simulation of Current Sheet Instabilities With Finite Guide Field and Comparison with Theory
AU: * Wang, X
EM: xywang@physics.auburn.edu
AF: Physics Department, Auburn University, Auburn, AL 36849,
AU: Lin, Y
EM: ylin@physics.auburn.edu
AF: Physics Department, Auburn University, Auburn, AL 36849,
AU: Chen, L
AF: Dept. Physics and Astronomy, University of California at Irvine, Irvine, CA 92697,
AU: Lin, Z
AF: Dept. Physics and Astronomy, University of California at Irvine, Irvine, CA 92697,
AU: Peter, Y
EM: yoonp@mail.umd.edu
AF: Institute for Physical Science and Technology, University of Maryland, College Park, MD 20742,
AU: Zhang, W
AF: Dept. Physics and Astronomy, University of California at Irvine, Irvine, CA 92697,
AB: The instability of current sheet under finite guide field (B_y) is investigated using our new gyrokinetic (GK) electron and fully kinetic (FK) ion particle simulation code, which resolves wave modes ranging from Alfvén waves to lower-hybrid/whistler waves. Compared with full-particle codes, the rapid electron cyclotron motion is removed in this model, wave-particle interactions preliminary simulation of Harris sheet is carried out in the 2D yz plane, with z being along the current sheet normal and anti-parallel B_x perpendicular to the simulation plane. The simulation has been performed with both a linearized (δ f) GKe/FKi code and the nonlinear code, for B_y/B_x=0.1-10. Under very small B_y, our results show LHDI modes at the current sheet edge propagating mainly in the y direction, as seen in previous simulations. As B_y increases, k_\perp and diamagnetic drift direction shift away from the current flow direction y. The LHDI modes become weaker while high frequency modes stronger. In the cases with a large B_y, the LHDI modes evolve to a globally propagating instability, and multiple ion cyclotron modes are excited. The simulations are performed for both purely electrostatic cases as well as electromagnetic cases. The mode properties obtained from the linear simulation are compared with those from theoretical calculations based on an electrostatic model. A more complete 3D simulation is planned to investigate the new physics introduced by the large guide field.
DE: 2723 Magnetic reconnection (7526, 7835)
DE: 2753 Numerical modeling
DE: 2772 Plasma waves and instabilities (2471)
DE: 7829 Kinetic waves and instabilities
DE: 7835 Magnetic reconnection (2723, 7526)
SC: SPA-Magnetospheric Physics [SM]
MN: 2007 Fall Meeting