HR: 1340h
AN: SM23B-0434 [Abstracts]
TI: Multilayer structure of thin current sheets in the Earth's magnetotail: The role of ionospheric
ions
AU: Zelenyi, L M
EM: lzelnyi@iki.rssi.ru
AF: Space Research Institute, Russian Academy of Sciences, Moscow, 117810
Russian Federation
AU: * Malova, H V
EM: mlv@dec1.sinp.msu.ru
AF: Space Research Institute, Russian Academy of Sciences, Moscow, 117810
Russian Federation
AU: * Malova, H V
EM: mlv@dec1.sinp.msu.ru
AF: Moscow State University, Physics, Moscow, 119899
Russian Federation
AU: Popov, V Y
SM23B-0434
AF: Moscow State University, Physics, Moscow, 119899
Russian Federation
AU: Delcourt, D C
SM23B-0434
AF: Centre d'etudes des Environnemonts Terrestres et Planetaires, CNRS, Saint-Mauer des Fau, 94107
France
AU: Ganushkina, N Y
SM23B-0434
AF: Finnish Meteorological Institute, Geophysical Research, Helsinki, 5
Finland
AU: Sharma, A S
EM: ssh@umd.edu
AF: University of Maryland, Astronomy, College Park, MD 20742
United States
AB:
Thin current sheets (TCS) represent one of the critical regions in the Earth's magnetosphere where magnetic energy accumulate
and is subsequently released. Self-consistent analytical models of multi-component TCS have been
developed by considering quasi-adiabatic approximation. In these equilibria the tension of magnetic field lines is balanced
by the ion inertia, rather than
the plasma pressure gradient. The influence of the electron population is taken into account assuming Boltzman- like
equilibrium distribution in the ambipolar electrostatic field. The electrostatic effects can lead to new and interesting
features of the current density profile inside the TCS, for example, to their splitting. Another effect is a very strong
steepening of the TCS magnetic field profile in the very center of the configuration. The presence of oxygen ions leads to a
contribution of less than 25 percent (for realistic magnetotail conditions) of the net cross- current, but the current
"wings" carried by O+ ions produce very noticeable thickening of the current profile. The dependencies of these effects on
the electron and oxygen temperatures, the relative density of O+ ions and the curvature of magnetic field lines are analyzed.
The implications of these effects for the problems of substorm triggering and particle acceleration are also investigated.
DE: 2744 Magnetotail
DE: 2764 Plasma sheet
DE: 2788 Magnetic storms and substorms (7954)
DE: 7827 Kinetic and MHD theory
DE: 7835 Magnetic reconnection (2723, 7526)
SC: SPA-Magnetospheric Physics [SM]
MN: Fall Meeting 2005