HR: 1330h
AN: SM43A-06    [Abstracts]
TI: Mirror Mode Waves Detected by Polar in Low Field Regions Near Midnight
AU: * Ge, Y
EM: ysge@ucla.edu
AF: University of California Los Angeles, Institute of Geophysics & Planetary Physics, 405 Hilgard Avenue, Los Angeles, CA 90095-1567 United States
AU: Russell, C T
EM: ctrussell@igpp.ucla.edu
AF: University of California Los Angeles, Institute of Geophysics & Planetary Physics, 405 Hilgard Avenue, Los Angeles, CA 90095-1567 United States
AB: The present study examines the magnetic field at the apogee of the Polar spacecraft when its apogee was close to the equatorial plane and within 2 hours in local time of midnight. In this region the magnetic field magnitude is rarely below 5 nT. However, when it is this low, it can become unstable to mirror mode oscillations which then reduce the field strength even lower locally to less than 2 nT. One interval of mirror mode waves caused the minimum total field to approach 1 nT. We survey their occurrence rate and the conditions that lead to their appearance.
DE: 2744 Magnetotail
DE: 2764 Plasma sheet
DE: 2772 Plasma waves and instabilities
SC: SPA-Magnetospheric Physics [SM]
MN: 2005 Joint Assembly