Field-aligned currents from asymmetric ring current during substorms

Abstract

First results of calculated distributions of field-aligned ion currents in the magnetosphere are given. The approach and equations developed by Gurevich and Tsedilina are applied. They were used for a previous estimation of electric fields in the ionosphere and magnetosphere, appearing in the process of the spreading of energetic particles, injected into the trapping zone in the magnetosphere as a result of nuclear explosion. According to this theory, energetic ions, injected into ring current, produce asymmetric divergent ring current and field-aligned currents, and global electric fields. The calculated field-aligned currents have a complicated spiral structure and can explain the results of measurements. Experimental measurements by the AMPTE/CCE spacecraft of energy and number density distributions of energetic particles in the ring current during the magnetic storm of Feb. 1986 were used for the modeling of field-aligned currents.