Mursula, K.,
Co-Authors: R. Kerttula, R. Friedel, P. Daly, T. Fritz, J. Blake, M. Grande, I. Sandahl, F. Snraas, M. Andre, and A. Balogh.,
Title: Cluster/Rapid energetic particle observations of the dayside magnetospheric boundary.,
Reference: European Geophysical Society meeting. Nice, April 2002.
Reference Type: Contributed Talk
CEPPAD: false
CAMMICE: false
RAPID: true
Abstract:
On the night between March 21/22, 2001, the Cluster satellites were flying outward in the high-latitude magnetosphere close to the noon sector, passing a magnetosheath/cusp type high density region at about 00 UT. Soon thereafter, at about 0030UT, they entered a region of high fluxes of energetic particles and a lower plasma density. Energetic particles were observed until about 03 UT when the satellites finally entered the magnetosheath. During the latter half of this 2.5h time interval the satellites observed three sudden dropouts of energetic particles, coinciding with the reappearance of high density magnetosheath type plasma. These changes indicate the oscillation of the dayside magnetospheric boundary layer and corresponded closely with the variations in the IMF direction. Using energetic particle observations we derive the speed and direction of motion of the dayside magnetospheric boundary layer. We show that the energetic particles have an anisotropic pitch angle distribution, indicating an acceleration of particles along the field line. We discuss these observations in terms of reconnection and the motion of the dayside boundary.
