Predicted energy spectra of ENAs produced as a result of charge exchange between interstellar neutral atoms and different ion populations present in the heliosheath, integrated along the LOS's of (a) Voyager 1 and (b) Voyager 2 (taken from the simulations of Zank et al. 2010). Purple: suprathermal ion tail with a kappa distribution; blue: transmitted solar wind (SW) ions; green: reflected heliosheath pickup ions (PUIs); dashed red: transmitted shell-like distribution of PUIs; dotted red: transmitted Maxwellian distribution of PUIs.