How Do κ-Distributed Protons in the Heliosheath Affect Energetic Neutral Atoms

Neutral hydrogen from interstellar space enters the heliosphere where it may charge-exchange with protons from the solar wind. This process introduces a slow cold proton (i.e. the original H-atom) into the plasma, whereupon it is accelerated by the motional electric field to become a pick-up ion. Simultaneously the original proton becomes a new H-atom that has an energy much higher than the original H-atom. In this work we assume the total proton population (i.e. core plus pick-up ions) downstream of the solar wind termination shock can be approximated as a κ-distribution, and numerically solve the coupled ion-neutral interaction between the solar wind and interstellar medium. We investigate the affect different values of the κ parameter have on the solution, and on the flux of energetic neutral atoms at Earth.