Influence of the ion losses on the generation of region 2 field-aligned currents

Pressure gradients created by the adiabatic convection of the magnetospheric plasma cannot completely explain the observed distribution at the planetary scale of region 2 field-aligned currents. The contribution of particle loss processes is evaluated. The assumption of a strong pitch-angle diffusion for both ions and electrons is shown to provide estimates comparable to the observed fluxes of soft precipitations. The efficiency of ion charge exchange is generally found to be weak relative to ion precipitation. These loss terms are included into a simplified fluid model of magnetospheric transport. The agreement with observations reveals the importance of losses, especially ion losses, in the generation of region 2 field-aligned currents