HR: 10:50h
AN: SM22A-03    [Abstracts]
TI: The Distant Magnetotail Under Long Duration, Very Northward IMF Conditions: October 22-24, 2003
AU: * Fairfield, D H
EM: Donald.H.Fairfield@nasa.gov
AF: Laboratory for Solar and Space Physics, NASA/GSFC, Code 612.3 NASA/GSFC, Greenbelt, MD 20771 United States
AU: Oieroset, M
EM: oieroset@ssk,ucb.edu
AF: Space Sciences Laboratory, University of California, Berkeley, UC Berkeley, Berkeley, CA 94720 United States
AU: Raeder, J
EM: j.raeder@und.edu
AF: Department of Physics and Space Science Center, University of New Hampshire, UNH, Durham, NH 03824 United States
AU: Lepping, R P
EM: Ronald.P.Lepping@nasa.gov
AF: Laboratory for Solar and Space Physics, NASA/GSFC, Code 612.3 NASA/GSFC, Greenbelt, MD 20771 United States
AB: A unique 32 hour interval of very northward Interplanetary Magnetic Field (IMF) on October 22-24, 2003 created a exceptionally thick cold dense magnetotail plasma sheet, a small polar cap and accompanying small tail lobe. These features were detected by the Cluster DMSP and FAST spacecraft and modeled by a global simulation as describe in recent papers by Oieroset et al. (2005) and Li et al. (2005). During the same interval the Wind spacecraft was passing through the center of the magnetotail about 130 Re downstream of Earth. Wind results that will be described reveal a very unusual magnetotail characterized by (1) continual tailward flow of 200-400 km/s with densities in the range 0.2-3/cc, both of which are clearly less than expected in the magnetosheath, (2) velocity waves of 100 to 200 km/s peak-to-peak amplitude and periods of 10 to 20 minutes superposed on the downstream flow, and (3) a mostly northward Bz magnetic field component with an often larger-magnitude Bx component whose sign reversal indicates crossings between the two hemispheres of the tail. The results appear to be consistent with the reported simulation that showed high latitude cusp reconnection and subsequent downtail flow of closed field lines, but the waves may be consistent with the Kelvin-Helmholtz instability often thought to occur during northward IMF conditions. Oieroset, M., J. Raeder,T. D. Phan, S. Wing, J. P. McFadden, W. Li, M. Fujimoto, H. Re`me, and A. Balogh (2005), Geophys. Res. Lett., 32, L12S07, doi:10.1029/2004GL021523. Li, W., J. Raeder, J. Dorelli, M. Oieroset, and T. D. Phan (2005), Geophys. Res. Lett., 32, L12S08, doi:10.1029/2004GL021524.
DE: 2740 Magnetospheric configuration and dynamics
DE: 2744 Magnetotail
DE: 2748 Magnetotail boundary layers
DE: 2764 Plasma sheet
SC: SPA-Magnetospheric Physics [SM]
MN: Fall Meeting 2005