HR: 0800h
AN: SM31B-05    [Abstracts]
TI: EXTREME MAGNETOSPHERE-IONOSPHERE COUPLING AT THE PLASMAPAUSE: A ONCE- IN-A-LIFETIME BRIGHT SAR ARC
AU: Baumgardner, J
EM: jeffreyb@bu.edu
AF: Boston University, 725 Commonwealth Ave., Boston, MA 02215, United States
AU: Wroten, J
EM: jwroten@bu.edu
AF: Boston University, 725 Commonwealth Ave., Boston, MA 02215, United States
AU: Semeter, J
EM: jls@bu.edu
AF: Boston University, 725 Commonwealth Ave., Boston, MA 02215, United States
AU: * Mendillo, M
EM: mendillo@bu.edu
AF: Boston University, 725 Commonwealth Ave., Boston, MA 02215, United States
AU: Kozyra, J
EM: jukozyra@umich.edu
AF: University of Michigan, 1414A Space Research Building, Ann Arbor, MI , United States
AB: Heat conduction from the ring current - plasmapause interaction region generates high electron temperature within the ionosphere that drive stable auroral red (SAR) arc emission at 6300 A. On the night of 29 October 1991, a SAR arc was observed using an all-sky imager and meridional imaging spectrograph at Millstone Hill. At xxxx UT, the SAR arc was south of Millstone at approximate L = 2 and reached emission levels of 13,000 rayleighs (R). Over two solar cycle of imaging observations have been made at Millstone Hill, and SAR arc brightness levels (excluding this event) averaged ~ 500 R. Simultaneous observations using the incoherent scatter radar (ISR), a DMSP satellite pass, the MSIS neutral atmosphere and SAR arc modeling using the Rees and Roble formalism succeeded in simulations of the observed emission. The reason for the unusual brightness was not the extreme temperatures achieved (and therefore heat conduction input), but the fact that the end of the plasmapause field line where the elevated Te values were measured did not occur in the ionospheric trough, but equatorward of it, thereby having far more ambient electrons to heat and subsequently collide with atomic oxygen. This unusual spatial geometry probably resulted from unusual convection patterns early in a superstorm scenario.
DE: 2730 Magnetosphere: inner
DE: 2778 Ring current
SC: SPA-Magnetospheric Physics [SM]
MN: 2007 Joint Assembly