On the Relationship between Auroral Zone X-ray Bursts and Polar Magnetic Substorms

Abstract

It is shown that auroral zone X-ray bursts of not too short duration are associated with the enhancement of the world-wide ionospheric current-system which after Silsbee and Vestine (1942) describes the latitude and longitude dependency of the geomagnetic bay, also called polar magnetic substorm (Akasofu and Chapman, 1963). This explains that the geomagnetic disturbances accompanying the X-ray bursts of local nature can always be recognized in the magnetograms of many stations, and also that they are sometimes very weak and even not recognizable at the very location where the X-ray bursts are measured overhead. The geomagnetic disturbance is, however, always the most pronounced at the stations with local time near midnight irrespective of the location of the associated X-ray burst.