HR: 08:18h
AN: SM11B-02 [Abstracts]
TI: Substorm plasma sheet ion pressure profiles
AU: * Wing, S
EM: simon.wing@jhuapl.edu
AF: Johns Hopkins University, 11100 Johns Hopkins Road, Laurel, MD 20723-6099, United
States
AU: Gjerloev, J W
EM: jesper.gjerloev@jhuapl.edu
AF: Johns Hopkins University, 11100 Johns Hopkins Road, Laurel, MD 20723-6099, United
States
AU: Johnson, J R
EM: jrj@pppl.gov
AF: Princeton University, POB 451 MS 28, Princeton, NJ 08543-0000, United States
AB:
The plasma sheet pressure, temperature, and density profiles inferred from DMSP observations are used to
investigate substorm growth, expansion, early-recovery, and late-recovery phases. During the growth phase, the
pressure peaks at the inner edge of the plasma sheet. The premidnight pressure peak is associated with the
temperature peak, while the postmidnight peak is associated with the density enhancement. After the substorm
onset, the pressure at the inner edge diminishes. Instead, the pressure peaks at premidnight from X = –10 to
–40 RE, which can be associated with temperature enhancement. During the early and late recovery phases, the
pressure peaks at postmidnight, which is associated with a cold, dense ion population, possibly resulting from
ion outflow and the substorm current systems. In the near-Earth region, the entropy decreases after substorm
onset, but the specific entropy appears to be roughly conserved.
DE: 2724 Magnetopause and boundary layers
DE: 2736 Magnetosphere/ionosphere interactions (2431)
DE: 2744 Magnetotail
DE: 2764 Plasma sheet
DE: 2790 Substorms
SC: SPA-Magnetospheric Physics [SM]
MN: 2007 Fall Meeting