On the magnetic field configuration of the magnetosheath

Abstract

The magnetosheath is the region where the shocked solar wind interacts directly with the magnetosphere. Here we examine the magnetic field throughout the equatorial magnetosheath as a function of the solar wind IMF direction using observational data sets (Geotail and Wind) spanning 9.5 years. In general, the synoptic maps of the magnetosheath magnetic field are in agreement with the predictions of Rankine-Hugoniot conditions at the bow shock and with global numerical models. Qualitative comparisons with recent analytic magnetosheath magnetic field models are also performed and show that the compression of the magnetosheath magnetic field between the two boundaries (bow shock and magnetopause) used in such models is greater than that which is observed.