Modeled IBEX/INCA skymaps including the keV-ENA source extinction in the outer heliosphere

TL;DR

This paper introduces a crucial correction called the source depletion effect for modeling IBEX/INCA skymaps, significantly improving the interpretation of ENA fluxes and the understanding of the outer heliosphere.

Contribution

It presents a new depletion correction in skymap modeling, enhancing the accuracy of heliospheric boundary reconstructions from ENA observations.

Findings

Depletion correction is essential for accurate ENA flux interpretation.

Including depletion correction alters the perceived shape of the heliospheric boundary.

Neglecting depletion leads to significant errors in boundary shape reconstruction.

Abstract

Understanding the outer heliospheric interface is a major challenge, especially in the light of recent observations by the IBEX and Voyager missions. We present further details on a new required theoretical correction that has been identified as substantial in a recent paper, the so-called source depletion effect. These results complement and expand earlier calculations of transit-time delays by presenting global skymaps of Energetic Neutral Atoms (ENAs) calculated with the depletion correction, comparing them with skymaps calculated without these corrections. Our results demonstrate that the depletion correction is critical for interpreting IBEX-Hi ENA fluxes generated in the inner heliosheath, and that any attempt to reconstruct the shape of the heliospheric boundary needs to include the depletion correction, unless arriving at considerably erroneous results.