HR: 10:50h
AN: SM42A-03 INVITED     [Abstracts]
TI: Intense Ion Outflow and its Association With Auroral Zone Alfven Wave Regions
AU: * Fuselier, S A
EM: stephen.a.fuselier@lmco.com
AF: Lockheed Martin Advanced Technology Center, Dept ADCS, Bldg 255 3251 Hanover St, Palo Alto, CA 94020, United States
AU: Claflin, E S
EM: claflin@spasci.com
AF: Lockheed Martin Advanced Technology Center, Dept ADCS, Bldg 255 3251 Hanover St, Palo Alto, CA 94020, United States
AB: In situ observations show that ion outflow occurs in three regions in the auroral zone. These three regions are the downward current region, upward current region, and Alfven wave region. Intense ion outflow in the Alfven wave region consists of ion conics with energies from ~10 to several 100 eV. The intensity of this outflow is typically an order of magnitude greater than the outflow from the other two auroral regions. Statistical studies of in situ data show that the outflow from the Alfven wave region extends over a broad range of local times that is approximately centered at ~0900 Magnetic Local Time. These studies require a minimum of several months of spacecraft in situ data to cover all local times in the auroral zone. This study investigates the instantaneous (~10 min time resolution) local time extent of ion outflow using neutral atom imaging from the IMAGE/Low Energy Neutral Atom imager. The instantaneous local time extent is compared to the results from statistical studies of in situ ion outflow data. In particular, the bias of the outflow to the dawnside (i.e., at the peak occurrence frequency of Alfven wave acceleration observations) is investigated as is the association between outflow and the location of the ionospheric footprint of the cusp.
DE: 2704 Auroral phenomena (2407)
DE: 2736 Magnetosphere/ionosphere interactions (2431)
DE: 2776 Polar cap phenomena
SC: SPA-Magnetospheric Physics [SM]
MN: 2007 Joint Assembly