Next: 1. Introduction
Initial POLAR MFE Observation of Substorm
Signatures in the Polar Magnetosphere
H. Kawano1, G. Le1, C. T. Russell1,
G. Rostoker2, T. Mukai3, H. Spence4, ...
1Institute of Geophysics and Planetary Physics,
University of California, Los Angeles,
Los Angeles, CA 90095-1567
2Department of Physics,
University of Alberta,
Edmonton, Alberta, T6G 2J1, Canada
3Institute of Space and Astronautical Science,
Sagamihara, Kanagawa 229, Japan
4Department of Astronomy and Center for Space Physics,
Boston University,
725 Commonwealth Ave.,
Boson, MA 02215
Abstract:
This paper studies substorm influences in the polar magnetosphere
using data from the POLAR magnetic field experiment (MFE).
The POLAR spacecraft remains in the high altitude polar magnetosphere for
extended periods around apogee. There it can stay
at nearly constant altitude
through all phases of a substorm, which was
not possible on previous missions. We
report such an event on March 28, 1996. Ground magnetometers monitored
substorm activity, while the POLAR spacecraft, directly over the pole
at (-0.8,-0.6,8.5) in GSM coordinates,
observed a corresponding perturbation
in the total magnetic field strength.
The total magnetic field first increased, then recovered
toward quiet levels, consistent with erosion of magnetic flux from
the dayside magnetosphere, followed by transport of that flux to the
magnetotail, and eventual onset of tail reconnection and the return
of that magnetic flux to the dayside magnetosphere.
Kawano Hideaki
Sat Jan 4 18:21:35 JST 1997