HR: 1340h
AN: SM53B-0410    [Abstracts]
TI: 3D Magnetic reconnection: evolution of x-lines.
AU: Driscoll, J
EM: name@server
AF: UCSD, UCSD, La Jolla, 92093 United States
AU: Karimabadi, H
EM: homa@san.rr.com
AF: UCSD, UCSD, La Jolla, 92093 United States
AU: Krauss-Verban, D
EM: name@server
AF: UCB, UCB, Berkeley, 94720 United States
AU: Huba, J
EM: huba@ppd.nrl.navy.mil
AF: NRL, NRL, Washington, 20375 United States
AU: Rudakov, L I
EM: name@server
AF: Berkeley Scholars Inc, Berkeley Scholars Inc, Beltsville, 20705 United States
AU: * Lapenta, G
EM: lapenta@lanl.gov
AF: LANL, LANL, Los Alamos, 87545 United States
AU: Ricci, P
EM: paolo.ricci@dartmouth.edu
AF: Dartmouth College, Dartmouth College, Hanover, 03755 United States
AB: In 3D reconnecting systems, the presence and evolution of x-points and x-lines play a crucial role in determining the topological transitions of the magnetic field [1]. Recently the attention has turned towards understanding the evolution of an initial perturbation in 3D where a current sheet is compressed in a localized region. Reconnection develops in the compressed region, forming an x-line. Subsequently, the x-line extends showing an anisotropic behaviour. Based on Hall-MHD theory, the electrons accelerated in the reconnection region and still tied to the field lines, bend the field lines in the current aligned direction leading to a domino effect that propagates the x-line in the electron direction (i.e. against the current) [2]. In contrast with the electron-dominated scenario, in presence of thicker sheet and for ion dominated current sheet, the process of x-line extension is observed to propagate in the opposite direction, following the ion motion. We will present a number of kinetic, hybrid, Hall-less hybrid and Hall-MHD simulations to clarify the issue and to determine the relative importance of the two effects. [1] Lau and Finn, Ap.J., 350, 672 (1990). [2] Huba and Rudakov, PoP, 9, 4435 (2002); Shay et al, GRL, 30, 1345 (2003)
DE: 7827 Kinetic and MHD theory
DE: 7835 Magnetic reconnection
DE: 7843 Numerical simulation studies
SC: SPA-Magnetospheric Physics [SM]
MN: 2004 AGU Fall Meeting