HR: 09:05h
AN: SM21C-05 [Abstracts]
TI: Highly periodic activations observed by THEMIS prior to substorm onset
AU: * Kepko, L
EM: larry.kepko@unh.edu
AF: Space Science Center, University of New Hampshire
Morse Hall
39 College Road, Durham, NH 03824, United States
AU: Raeder, J
EM: j.raeder@unh.edu
AF: Space Science Center, University of New Hampshire
Morse Hall
39 College Road, Durham, NH 03824, United States
AU: Angelopoulos, V
EM: vassilis@ssl.berkeley.edu
AF: Space Sciences Laboratory, University of California at Berkeley, Berkeley, CA 94720, United
States
AU: Carlson, C
EM: cwc@ssl.berkeley.edu
AF: Space Sciences Laboratory, University of California at Berkeley, Berkeley, CA 94720, United
States
AU: Frey, H
EM: hfrey@ssl.berkeley.edu
AF: Space Sciences Laboratory, University of California at Berkeley, Berkeley, CA 94720, United
States
AU: Larson, D
EM: davin@ssl.berkeley.edu
AF: Space Sciences Laboratory, University of California at Berkeley, Berkeley, CA 94720, United
States
AU: McFadden, J
EM: mcfadden@ssl.berkeley.edu
AF: Space Sciences Laboratory, University of California at Berkeley, Berkeley, CA 94720, United
States
AU: Mende, S
EM: mende@ssl.berkeley.edu
AF: Space Sciences Laboratory, University of California at Berkeley, Berkeley, CA 94720, United
States
AU: Parks, G
EM: parks@ssl.berkeley.edu
AF: Space Sciences Laboratory, University of California at Berkeley, Berkeley, CA 94720, United
States
AU: Glassmeier, K
EM: kh.glassmeier@tu-bs.de
AF: Institute of Geophysics and Extraterrestrial Physics, Technical University of Braunschweig,
Braunschweig, MA 38106, Germany
AU: Auster, U
EM: uli.auster@tu-bs.de
AF: Institute of Geophysics and Extraterrestrial Physics, Technical University of Braunschweig,
Braunschweig, MA 38106, Germany
AU: Donovan, E
EM: eric@phys.ucalgary.edu
AF: University of Calgary, SB 605 University of Calgary
2500 University Drive NW, Calgary, AB T2N1N4, Canada
AU: Russell, C
EM: ctrussell@igpp.ucla.edu
AF: Institute of Geophysics and Planetary physics, University of California, Los Angeles, Los
Angeles, CA 90095, United States
AU: Ge, Y
EM: ysge@igpp.ucla.edu
AF: Institute of Geophysics and Planetary physics, University of California, Los Angeles, Los
Angeles, CA 90095, United States
AU: Mann, I
EM: imann@phys.ualberta.ca
AF: Department of Physics, University of Alberta
11322-89 Avenue, Edmonton, AB T6G 2G7, Canada
AU: Henderson, M
EM: mghenderson@lanl.gov
AF: Los Alamos National Laboratory, Space Science and Applications Group ISR-1, Los
Alamos, NM 87545, United States
AU: Yumoto, K
EM: yumoto@serc.kyushu-u.ac.jp
AF: Space Environment Research Center, Kyushu University, Hakozaki, Fukuoka, MA 812-
8581, Japan
AU: Singer, H
EM: howard.singer@noaa.gov
AF: NOAA Space Environment Center, 325 Broadway, Boulder, CO 80305, United States
AB:
On March 24, 2007, the THEMIS spacecraft observed near the dusk flank several 10 minute quasi-periodic flow
and magnetic field oscillations followed by the onset of a strong substorm. The IMF was strongly southward
during the event, although the start of the oscillations appeared to be associated with a brief but significant
northward turning. Each of the oscillations was accompanied by an auroral intensification, an energetic particle
injection, and ground Pi2 pulsations. We first characterize the timing of the events observed by the 5 THEMIS
spacecraft, ground imagers and magnetometers, and geosynchronous spacecraft. We then examine whether the
quasi-periodic activations were manifestations of an instability that lead to the onset of a global substorm.
DE: 2740 Magnetospheric configuration and dynamics
DE: 2760 Plasma convection (2463)
DE: 2764 Plasma sheet
DE: 2788 Magnetic storms and substorms (7954)
DE: 2790 Substorms
SC: SPA-Magnetospheric Physics [SM]
MN: 2007 Fall Meeting