HR: 1340h
AN: SM23A-1178    [Abstracts]
TI: Observed Tail Current Systems Associated with Bursty Bulk Flows and Auroral Streamers During a Period of Multiple Substorms
AU: * Forsyth, C
EM: cf50@ion.le.ac.uk
AF: University of Leicester, Dept. Physics and Astronomy, University of Leicester, University Road, Leicester, LE1 7RH, United Kingdom
AU: Lester, M
EM: mle@ion.le.ac.uk
AF: University of Leicester, Dept. Physics and Astronomy, University of Leicester, University Road, Leicester, LE1 7RH, United Kingdom
AU: Cowley, S W
EM: swhc1@ion.le.ac.uk
AF: University of Leicester, Dept. Physics and Astronomy, University of Leicester, University Road, Leicester, LE1 7RH, United Kingdom
AU: Dandouras, I
EM: Iannis.Dandouras@cesr.fr
AF: CESR/CNRS, 9 Avenue du Colonel Roche, B.P. 4346, Toulouse, F-31028, France
AU: Fazakerley, A N
EM: anf@mssl.ucl.ac.uk
AF: University College London, Mullard Space Science Laboratory, University College London, Holmbury St. Mary, Dorking, RH5 6NT, United Kingdom
AU: Fear, R C
EM: rcf11@ion.le.ac.uk
AF: University of Leicester, Dept. Physics and Astronomy, University of Leicester, University Road, Leicester, LE1 7RH, United Kingdom
AU: Frey, H U
EM: hfrey@ssl.berkeley.edu
AF: University of California, Space Sciences Laboratory, University of California, Berkeley, CA 94720, United States
AU: Grocott, A
EM: ag27@ion.le.ac.uk
AF: University of Leicester, Dept. Physics and Astronomy, University of Leicester, University Road, Leicester, LE1 7RH, United Kingdom
AU: Kadokura, A
EM: kadokura@nipr.ac.jp
AF: National Institute of Polar Research, 9-10-1 Kaga, Itabashi, Tokyo, 173-8515, Japan
AU: Lucek, E A
EM: e.lucel@imperial.ac.uk
AF: Imperial College, Blackett Laboratory, Imperial College, London, SW7 2BZ, United Kingdom
AU: Réme, H
EM: Henri.Reme@cesr.fr
AF: CESR/CNRS, 9 Avenue du Colonel Roche, B.P. 4346, Toulouse, F-31028, France
AU: Milan, S E
EM: ets@ion.le.ac.uk
AF: University of Leicester, Dept. Physics and Astronomy, University of Leicester, University Road, Leicester, LE1 7RH, United Kingdom
AU: Milan, S E
EM: ets@ion.le.ac.uk
AF: CESR/CNRS, 9 Avenue du Colonel Roche, B.P. 4346, Toulouse, F-31028, France
AU: Watermann, J
EM: jfw@dmi.dk
AF: Danish Meteorological Institute, Atmosphere Space Research Division, Danish Meteorological Institut, Copenhagen, DK-2100, Denmark
AB: We present a multi-instrument study of a substorm bursty bulk flow (BBF) and auroral streamer. During a substorm on the 25 August 2003, which was one of a series of substorms that occurred between 00:00 and 05:00~UT, the Cluster spacecraft encountered a BBF event travelling Earthwards and duskwards with a velocity of ~500~{km~s^-1} some nine minutes after the onset of the substorm. Coincident with this event the IMAGE spacecraft detected an auroral streamer in the substorm auroral bulge in the southern hemisphere near the footpoints of the Cluster spacecraft. Using FluxGate Magnetometer (FGM) data from the four Cluster spacecraft, we determine the field-aligned currents in the BBF, using the curlometer technique, to have been ~5~{mA~km^-2}. When projected into the ionosphere, these currents give ionospheric field-aligned currents of ~ 18~{A~km^-2}, which is comparable with previously observed ionospheric field-aligned current associated with BBFs and auroral streamers. The observations of the BBF are consistent with the plasma "bubble" model of Chen and Wolf (1993) and with the reconnection of open field-lines Earthward of the substorm associated near-Earth neutral line for the creation of BBFs.
DE: 2700 MAGNETOSPHERIC PHYSICS (6939)
DE: 2704 Auroral phenomena (2407)
DE: 2721 Field-aligned currents and current systems (2409)
DE: 2744 Magnetotail
DE: 2790 Substorms
SC: SPA-Magnetospheric Physics [SM]
MN: 2007 Fall Meeting