HR: 0800h
AN: SM31B-0418 [Abstracts]
TI: Magnetic Reconnection in Global MHD Modeling of Magnetosphere
Dynamics
AU: * Kuznetsova, M M
EM: masha@elbrus.gsfc.nasa.gov
AF: NASA Goddard Space Flight Center, Code 612.3, Greenbelt, MD 20771
United States
AU: Hesse, M
SM31B-0418
AF: NASA Goddard Space Flight Center, Code 612.3, Greenbelt, MD 20771
United States
AU: Rastatter, L
SM31B-0418
AF: NASA Goddard Space Flight Center, Code 612.3, Greenbelt, MD 20771
United States
AU: Toth, G
SM31B-0418
AF: University of Michigan, 2455 Hayward St., Ann Arbor, MI 48109
United States
AU: De Zeeuw, D
SM31B-0418
AF: University of Michigan, 2455 Hayward St., Ann Arbor, MI 48109
United States
AU: Gombosi, T
SM31B-0418
AF: University of Michigan, 2455 Hayward St., Ann Arbor, MI 48109
United States
AB:
One of the major challenges in global MHD modeling of magnetosphere
dynamics is to find an
accurate description of the reconnection rate. We will take advantage of
recent
progress in small-scale kinetic studies of magnetic reconnection, which
demonstrated
that the reconnection rate is controlled by ion nongyrotropic behavior near the
reconnection site. It can then be expressed in terms of nongyrotropic
corrections to the
electric field. We will demonstrate that the reconnection electric field
can be
estimated as a convection electric field v x B at the edge of the non-MHD
diffusion
region. The BATSRUS adaptive grid structure allows to perform global
simulations with
spatial resolution near the reconnection site comparable with ion kinetic
scales. To
reproduce fast reconnection rates observed in kinetic simulations we
modified the
global MHD code BATSRUS by introducing nongyrotropic corrections to the
magnetic
induction equation. The role of the nongyrotropic effects near the
reconnection site
on the global magnetospheric dynamics will be analyzed. Testing the
ability of global
MHD models to describe magnetospheric dynamics is one of the elements of
science based validation efforts at the Community Coordinated Modeling Center.
DE: 2700 MAGNETOSPHERIC PHYSICS (6939)
DE: 2723 Magnetic reconnection (7526, 7835)
DE: 2784 Solar wind/magnetosphere interactions
DE: 7827 Kinetic and MHD theory
DE: 7835 Magnetic reconnection (2723, 7526)
SC: SPA-Magnetospheric Physics [SM]
MN: Fall Meeting 2005