Potential mapping method for the steady-state magnetosheath model

Abstract. We present the potential mapping method which is a model of steady-state flow velocity and magnetic field in the empirical magnetosheath domain. The method makes use of a coordinate transformation from the empirical magnetosheath domain into the parabolic magnetosheath domain, and evaluate a set of the shell variable and the connector variable to utilize the solution of Laplace equation obtained for the parabolic magnetosheath domain. Our model uses two invariants of transformation: the zenith angle in the magnetosheath and the ratio of the distance to the magnetopause to the thickness of magnetosheath along the magnetopause-normal direction. The plasma flow and magnetic field can be determined as a function of the upstream condition (flow velocity or magnetic field) in a wider range of zenith angle. The potential mapping method is computationally inexpensive by using the analytic expression as much as possible, is applicable to the planetary magnetosheath domains.