On application of asymmetric Kan-like exact equilibria to the Earth magnetotail modeling

A new class of solutions of the Vlasov-Maxwell equations is developed by means of generalization of the well-known Harris-Fadeev-Kan-Manankova family of exact two-dimensional equilibria. The new model reproduces the current sheet bending and shifting in the vertical plane, arising from the Earth dipole tilting and the solar wind non-radial propagation. The generalized model allows magnetic configurations with equatorial magnetic field decreasing in tailward direction as slow as 1/ x , contrary to the original Kan model (1/ x 3 ); magnetic configurations with a single X-point are also available. The analytical solution is compared with the empirical T96 model in terms of the magnetic flux tube volume. It is found that parameters of the analytical model may be adjusted to fit a wide range of realistic current sheets. The best agreement between analytical and empirical models is obtained for the midtail at distances beyond 10–15  R E at high levels of magnetospheric activity.