Comparison between IBEX-Hi ENA spectra (in black) with the ENA spectra predicted by Zank et al. (2010) along the LOS's of the two Voyager spacecraft. Green: suprathermal ion tail with a kappa distribution; blue: sum of transmitted SW ions, reflected heliosheath PUIs, and transmitted Maxwellian distribution of PUIs; red: sum of transmitted SW ions, reflected heliosheath PUIs, and transmitted shell-like distribution of PUIs. Panels (c) and (d) compare the energy dependence of the spectral indices measured by IBEX-Hi (from Figure  2(b)) with that seen in the ENA populations created by the three different types of ion populations.