HR: 1330h
AN: SM23B-11    [Abstracts]
TI: Clock Angle Dependence of Magnetic Reconnection at Earth's Subsolar Magnetopause
AU: * Dorelli, J C
EM: john.dorelli@unh.edu
AF: UNH EOS Space Science Center, 245E Morse Hall 39 College Road, Durham, NH 03824 United States
AU: Raeder, J
EM: J.Raeder@unh.edu
AF: UNH EOS Space Science Center, 245E Morse Hall 39 College Road, Durham, NH 03824 United States
AB: We use global magnetohydrodynamics (MHD) simulations to investigate the clock angle dependence of magnetic reconnection at Earth's subsolar magnetopause. Under steady solar wind conditions, and when the plasma resistivity is constant, we find that reconnection occurs at the subsolar magnetopause via a flux pileup mechanism for both northward and southward interplanetary magnetic field (IMF) conditions. Magnetic energy accumulates upstream of a Sweet-Parker current sheet to accommodate the sub-Alfvénic magnetosheath flow, and the upstream plasma density decreases (forming a plasma depletion layer) in order to satisfy momentum conservation. We argue, therefore, that in the context of resistive MHD, plasma depletion upstream of the magnetopause is a signature of magnetic flux pileup reconnection which occurs at the subsolar magnetopause under both northward and southward IMF conditions. We discuss the implications of these results for the "component" vs. "antiparallel" merging debate as well as for the interpretation of spacecraft observations of the plasma depletion layer.
DE: 2724 Magnetopause, cusp, and boundary layers
DE: 2753 Numerical modeling
DE: 7835 Magnetic reconnection
SC: SPA-Magnetospheric Physics [SM]
MN: 2005 Joint Assembly