Turbulence and ion heating in the heliosheath and implications for energetic neutral atoms

All-sky maps of energetic neutral atoms (ENAs) have revealed significant gaps in our understanding of the heliospheric plasma. At low energies around 100 eV, current ENA models underpredict the observed ENA flux by more than an order of magnitude in all directions. Here, we present an investigation into the effects of turbulence on ions in the heliosheath region between the termination shock and the heliopause. The heliosheath is a unique environment with a high plasma beta and multiple ion components that have distinct temperatures. Using hybrid kinetic simulations, we find that turbulence causes strong ion heating and velocity fluctuations, leading to an increase of the charge-exchange source of low-energy ENAs. However, the effects are likely not strong enough to completely explain the observations, pointing to the need for further investigations.