HR: 15:20h
AN: P53B-07    [Abstracts]
TI: Interchange Injection and Drift Dispersion of Hot Plasma in Saturn's Magnetosphere
AU: * Hill, T W
EM: hill@rice.edu
AF: Rice University, MS 108, Houston, TX 77005 United States
AU: Burch, J L
AF: Southwest Research Institute, P. O. Drawer 28510, San Antonio, TX 78228-0510 United States
AU: Crary, F J
AF: Southwest Research Institute, P. O. Drawer 28510, San Antonio, TX 78228-0510 United States
AU: Thomsen, M F
AF: Los Alamos National Laboratory, MS D466, Los Alamos, NM 87545 United States
AU: Delapp, D
AF: Los Alamos National Laboratory, MS D466, Los Alamos, NM 87545 United States
AU: Rymer, A M
AF: Mullard Space Science Laboratory, Holmbury St. Mary, Dorking, Sur RH5 6NT United Kingdom
AU: Coates, A J
AF: Mullard Space Science Laboratory, Holmbury St. Mary, Dorking, Sur RH5 6NT United Kingdom
AU: Young, D T
AF: Southwest Research Institute, P. O. Drawer 28510, San Antonio, TX 78228-0510 United States
AU: Bolton, S J
AF: Jet Propulsion Laboratory, 4800 Oak Grove Drive, MS 230-205, Pasadena, CA 91109 United States
AU: Sittler, E C
AF: NASA Goddard Space Flight Center, MC 692, Greenbelt, MD 20771 United States
AB: During the first pass of the Cassini-Huygens spacecraft through Saturn's magnetosphere, the Cassini Plasma Spectrometer (CAPS) observed several intermittent occurrences of multi-keV ions and electrons superimposed on a cooler (10 - 100 eV) background plasma. These events are tentatively interpreted as signatures of centrifugally driven interchange motions that inject isolated flux tubes of hot tenuous plasma toward Saturn, similar to injection events reported at Jupiter by the Galileo spacecraft. Both ions and electrons show evidence of energy-time dispersion resulting from adiabatic (gradient-curvature) drift relative to the partially corotating plasma frame of reference. Rotation converts a longitude structure in the rotating frame into a temporal structure in the spacecraft frame. Ions (electrons) drift eastward (westward) relative to the rotating frame with a speed proportional to thermal energy. Thus ions (electrons) display a negative (positive) slope in an energy-time spectrogram. The magnitude of the slope is a measure of the elapsed time since injection. Such events are observed both inbound and outbound in a radial range L = 6 - 10, and are frequently associated with narrow but deep density cavities in the cooler background plasma.
DE: 5443 Magnetospheres (2756)
DE: 5737 Magnetospheres (2756)
DE: 2720 Energetic particles, trapped
DE: 2756 Planetary magnetospheres (5443, 5737, 6030)
SC: Planetary Sciences [P]
MN: 2004 AGU Fall Meeting