HR: 11:45h
AN: SM12B-06 [Abstracts]
TI: Particle Transport From the Plasma Sheet to the Ring Current
Region and Ring Current Development Under the Influence of
Substorm-Associated Electric Fields
AU: * Ganushkina, N Y
EM: Nataly.Ganushkina@fmi.fi
AF: Finnish Meteorological Institute, Space research, P.O.Box 503 (Vuorikatu 15 A), Helsinki, FIN-00101
Finland
AU: Pulkkinen, T T
EM: Tuija.Pulkkinen@fmi.fi
AF: Finnish Meteorological Institute, Space research, P.O.Box 503 (Vuorikatu 15 A), Helsinki, FIN-00101
Finland
AB:
The coupling between plasma populations, namely, the ring current and the plasma sheet, is analyzed in the frame of study on
the storm-time ring current response and development under the influence of substorm-associated electric fields. We model the
proposed periods of April-June 2001 and April 2002 storm. We trace particles with arbitrary pitch angles numerically in the
drift approximation. Tracing is performed in different realistic time-dependent magnetic and electric field models.
Substorm-associated electric field is given by Gaussian pulse with azimuthal field component propagating inward with a
velocity dependent on radial distance. The magnetic field from this pulse is calculated by Faraday's law. We model particle
inward motion and energization by a series of electric field pulses representing substorm activations during storm events.
The obtained model Dst index, energy density and particle flux maps are then compared to ground-based and satellite
observations such as ground-based magnetic field and IMAGE, LANL, CLUSTER particle measurements. The role of
substorm-associated fields in the energization of the plasma sheet particles to higher energies (more than 100 keV) and their
transport inward to closed drift shells is closely studied.
DE: 2778 Ring current
DE: 2788 Storms and substorms
SC: SPA-Magnetospheric Physics [SM]
MN: 2004 AGU Fall Meeting