Bemerkungen zur Hypothese zweier Sturmzeitringströme

Summary

For several years the theory of the main phase of geomagnetic storms takes into account the existence of two storm time ring currents which are thought to exist in different altitudes. This hypothesis is supported less by satellite data than by the analysis of recovery effects observed in the geomagnetic records, according to that the recovery phase should exist of two seperate single phases. In our opinion however the observational material seems not convincing enough, especially because material of one station only was used for the hitherto made investigations and no elimination of theSq-part was executed. A critical analysis of the observational material is by all means necessary, especially for the reason that already in literature extensive inferences of theDR2 ring current for the formation and the energy behaviour of theDP part were drawn. For the investigation of recovery effects it is necessary to use additionally to records of equatorial stations those of observatories in higher latitudes. TheSq-part has to be eliminated in the analysis. It is referred that new disturbances after the beginning of the recovery phase can feign two separated ring current effects. Some examples of the recovery phase will be discussed. They show that the observational material gives no necessity for the supposition of two separate strom time ring currents. Furthermore some theoretical considerations are opposite to this hypothesis. The charge exchange with thermical atoms of hydrogen is discussed to be a possible loss process. It is taken into account also the possibility to suppose a wide proton energy spectrum for explaining the recovery phase.