HR: 1340h
AN: SM23B-0432    [Abstracts]
TI: Thin Current Sheets and Reconnection Onset in low Beta Plasmas
AU: * Krauss-Varban, D
EM: varban@ssl.berkeley.edu
AF: SSL, UC Berkeley, 7 Gauss Way, Berkeley, CA 94720-7450 United States
AU: Lapenta, G
EM: lapenta@lanl.gov
AF: Los Alamos National Laboratory, K717, Los Alamos, NM 87545 United States
AU: Delzanno, G L
EM: delzanno@lanl.gov
AF: Los Alamos National Laboratory, K717, Los Alamos, NM 87545 United States
AB: Magnetic field line reconnection in the solar wind and in the corona can take place under very low beta conditions. One of the outstanding questions is, whether in these cases reconnection actually initiates in a low beta current sheet. For example, this is not the case in the near-Earth tail, where the cold plasma lobes are separated by a hot plasma sheet. Thus, although the lobes are cold, the configuration is observationally known to be reasonably well described by a conventional Harris equilibrium with a cold background population. In part, the problem of reconnection onset in low beta plasmas has not been extensively studied due to a lack of known, appropriate equilibria. But more importantly, there is little understanding of how thin current sheets develop and evolve in a low beta plasma, the first place. Here, we investigate the formation of thin current sheets and the ensuing evolution of approximate equilibria with one-dimensional and two-dimensional hybrid simulations (electron fluid, kinetic ions). At first, we concentrate on the parameter regime where the ion gyro radius is much smaller than the ion inertial length, but not smaller than the electron inertial length. We will report on methods to use our results in the construction of appropriate full-particle simulations of reconnection onset.
DE: 2109 Discontinuities (7811)
DE: 2723 Magnetic reconnection (7526, 7835)
DE: 7526 Magnetic reconnection (2723, 7835)
DE: 7827 Kinetic and MHD theory
DE: 7835 Magnetic reconnection (2723, 7526)
SC: SPA-Magnetospheric Physics [SM]
MN: Fall Meeting 2005