HR: 10:35h
AN: SM52A-02 INVITED     [Abstracts]
TI: Visualizing Three-dimensional Magnetic Reconnection in the Magnetosphere
AU: * Dorelli, J
EM: john.dorelli@unh.edu
AF: EOS Space Science Center University of New Hampshire, 39 College Road, Durham, NH 03824 United States
AU: Raeder, J
EM: J.Raeder@unh.edu
AF: EOS Space Science Center University of New Hampshire, 39 College Road, Durham, NH 03824 United States
AU: Larson, D
EM: djl@space.unh.edu
AF: EOS Space Science Center University of New Hampshire, 39 College Road, Durham, NH 03824 United States
AU: Fogal, T
EM: tfogal@apollo.sr.unh.edu
AF: EOS Space Science Center University of New Hampshire, 39 College Road, Durham, NH 03824 United States
AB: We address the problem of visualizing three-dimensional magnetic reconnection in the magnetosphere. We present results from calculations of the magnetic skeleton (i.e., the system of magnetic nulls, separator lines and separatrix surfaces which uniquely characterize the magnetic field topology) of the magnetosphere for various IMF orientations. A robust method of locating and tracking magnetic null points is described. The algorithm, based on a bisection method invented by John Greene [J. Comp. Phys., 98, 1992], computes the topological dimension of the magnetic vector field at each cell of the computational grid. The method is very robust, requiring only the values of the magnetic field on the grid points defining each cell. Once the null points are located, we use two separate methods to compute the magnetic separator lines: 1) a shooting method where an initial magnetic seed point is varied until the associated magnetic field line passes as close as possible to one or more of the other nulls; 2) computation of the intersections of the "fan" surfaces associated with the nulls. Three dimensional visualization of the magnetic skeleton, along with isosurfaces of the current density, allow us compare our simulation results to the various competing models of three-dimensional magnetic reconnection in the magnetosphere.
DE: 7835 Magnetic reconnection
DE: 7843 Numerical simulation studies
DE: 2753 Numerical modeling
DE: 2784 Solar wind/magnetosphere interactions
SC: SPA-Magnetospheric Physics [SM]
MN: 2004 AGU Fall Meeting