On the ion-scale structure of thin current sheets in the magnetotail

A numerical and analytical investigation of the formation and structure of thin current sheets which form in a magnetotail-like plasma model is presented. Current sheet formation is driven by the application of a boundary electric field similar to what would be expected from solar wind driving. As a result, a thin current sheet forms which involves strong Hall-type electric fields, which, by means of electric field drifts, strongly increase the electron contribution, and reduce the ion contribution to the cross-tail current density. This result is also supported by analytical investigations of the total plasma momentum. The thin current sheet forms on strong gradients in the ion density and the magnetic field. The simulation leads to a well defined equilibrium state.