The north-south asymmetry of the solar and heliospheric magnetic field during activity minima

Recent in situ spacecraft observations and the analysis of the galactic cosmic ray intensity at Earth have shown that the heliospheric magnetic field exhibited a north-south asymmetry and that the heliospheric current sheet was inclined with respect to the solar equator during the years around the last sunspot minimum (1995-1996). In this paper we show that both heliospheric characteristics are due to the particular way the solar magnetic field evolves. The north-south asymmetry can be explained with the evolution of the quadrupolar component of the field in the solar magnetosphere and the inclination of the heliospheric current sheet could be a result of the presence of an inclined relic dipolar field in the Sun, as has been suggested by Bravo and Stewart [1995].