Secular Variations of a Shift of the Heliospheric Current Sheet

Abstract

The shift of the heliospheric current sheet (HCS) can be judged by the correlation between polarities of the interplanetary magnetic field (IMF) observed near the Earth. Here the IMF polarities which were reconstructed from the geomagnetic data of the mid-latitude stations beginning from 1844 are studied. The correlation of positive and negative IMF sectors is the evidence of a shift of the heliospheric current sheet towards the Northern Hemisphere in cycles 15–19 of solar activity, and towards the south, in cycles 10–14. We suggest that there is a regular secular cycle of the south–north asymmetry of the current sheet. Correspondingly, a similar cycle is also characteristic of the solar magnetic field.