Diagnosing the magnetospheric plasma structures using relativistic electron data

Abstract

The behaviour of simultaneously measured near-equatorial ring current ions and relativistic electrons, in the course of strong magnetic storm, is analyzed. As appears, the injection of relativistic electrons into the slot region is occurred on time scale ∼ 1 hour when the extremely low latitude position of auroral electrojets is reached and the ring current becomes more symmetrical. Positions of the ring current maximum and electron intensity maximum (Lmax) correspond to our previous result: ∥Dst∥max = 2.75·104Lmax4 . An extreme storm-time low-latitude position of the west electrojet center (for amplitudes of ∥Dst∥max up to 600 nT) is shown to be in a good consistence with this empirical dependence. It is supposed the trapped radiation boundary collapses down to L ∼ Lmax in the course of the storm main phase. The conception of “main” substorm has been developed. This substorm is defined as one that has the lowest latitude of the west electrojet center among all substorms of this magnetic storm.