Pick-up ions upstream and downstream of the termination shock

Hydrogen pick-up ions produced in the inner heliosphere are convected outwa rds with the solar wind and suffer energy-diffusion by quasilinear wave-par ticle interactions. When arriving at the solar wind termination shock, the big majority of these pick-up's passes directly from the preshock to the po stshock plasma regime. While crossing the shock these ions suffer a charact eristic change in their density and velocity distribution which sensitively reflects the local shock properties. We extend the earlier model calculati ons to derive the pre-shock and postshock pick-up proton spectrum in the ec liptic plane, taking into account the global structure of the heliosphere a nd the termination shock. The proton distribution is used to calculate the energetic neutral hydrogen flux and the results are compared with the CELIA S/HSTOF data. There is a satisfactory agreement as regards the flux intensi ty scale and the directional dependence of the flux. The calculated energy spectrum is steeper than the data.