Hybrid Simulations for Pickup Ion Distributions at the Termination Shock

In this paper we focus on hybrid simulations, which were performed in order to support data analysis and interpretation of Voyager data and most recent IBEX observations. Two‐dimensional multi‐species hybrid simulations for the termination shock have been performed in which we used almost realistic plasma parameters. In these simulations we included self‐consistently solar wind protons and pickup protons. We investigated the change of the turbulence around and at the shock front as well as spatial and temporal evolution of the solar wind proton distribution under the impact of pickup protons. The results of this study show that pickup ions have a significant impact. Pickup ions mediate the shock turbulence, ion reflection, thermalization, and also slow down incoming solar wind. Furthermore, these simulations also show that gyrating solar wind and pickup ions may be a significant source for Energetic Neutral Atoms (ENAs).