A model of the steady state magnetic field in the magnetosheath

Abstract

For given parameters of the interplanetary plasma near Earth the magnetic field in the magnetosheath can be described by fluctuations superimposed upon an average static field configuration. Using potential theory, we derived analytical expressions describing the steady state magnetic field in the transition region between the bow shock and the magnetopause. The model contains five parameters, namely, the stand‐off distance of the magnetopause, the stand‐off distance of the bow shock, and the three components of the interplanetary magnetic field. The shape of the magnetopause and of the bow shock is modeled by a paraboloid with rotational symmetry around the Sun‐Earth axis. Compared to other models, our procedure leads to simple analytical formulae which make it most suitable for studies of the effects of the magnetosheath on charged particle propagation.