Physics
Scientific paper
May 2001
adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2001jastp..63..657b&link_type=abstract
Journal of Atmospheric and Solar-Terrestrial Physics, Volume 63, Issue 7, p. 657-670.
Physics
1
Scientific paper
Magnetospheric energetics during substorm events is studied in this paper. Three events were selected, a weak substorm, a large isolated one and finally a prolonged period of substorm activity with multiple intensifications. It is assumed that the energy, that entered the magnetosphere due to electromagnetic coupling with the solar wind, is described by the epsilon parameter, proposed by Perreault and Akasofu (1978). High resolution, magnetic field and plasma data from the MGF and LEP experiments on board GEOTAIL were analyzed to determine the timing of plasmoid release, its dimensions, its convection velocity and finally the energy carried by each plasmoid. Plasmoids were defined as structures with rotating magnetic fields and enhanced total pressure. Tailward plasmoid bulk speed in the distant tail varied from 350 to 750km/s. Their dimensions in XGSM direction was found to be from 4.5 to 28Re, and their duration did not exceed 5min. The average energy carried by each plasmoid in the distant tail was estimated to be equal to (2.4+/-1.0)×1014J. The thermal energy flux dominates when the plasmoid structure is a closed loop. In cases of flux rope plasmoids the kinetic energy is comparable to or even greater than the thermal energy flux. The study of the overall magnetospheric energetics yielded the result that the input solar wind energy, estimated by the integral of the epsilon parameter over the lifetime of a substorm, represents the energy stored in the magnetotail and the convective dissipation in the ionosphere as well. The energy required for the plasmoid release is thought to be provided by the night side reconnection in the near-Earth neutral line location. Finally, it was found that 20% of the total input solar wind energy is dissipated in the auroral ionosphere.
Belehaki Anna
Tsagouri Ioanna
No associations
LandOfFree
Magnetosphere energetics during substorm events: IMP8 and GEOTAIL observations does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with Magnetosphere energetics during substorm events: IMP8 and GEOTAIL observations, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Magnetosphere energetics during substorm events: IMP8 and GEOTAIL observations will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-941762