THE IMPRINT OF THE VERY LOCAL INTERSTELLAR MAGNETIC FIELD IN SIMULATED ENERGETIC NEUTRAL ATOM MAPS

The interaction of the solar wind with the very local interstellar medium (VLISM) forms the boundaries of the heliosphere. A strong asymmetry of the heliosphere was found both directly by the Voyager probes and indirectly from measurements of the deflection of neutral hydrogen. The most likely source of this asymmetry is from the interstellar magnetic field, the properties of which are highly unconstrained. Energetic neutral atom (ENA) images will provide an additional method to view the heliosphere and infer the interstellar magnetic field. This paper investigates the imprint of the interstellar magnetic field on simulated energetic neutral atom all-sky maps. We show that a significant source of 0.5-1 keV ENAs may originate from the outside of the heliopause, if a strong suprathermal population exists in the VLISM. In simulations, a strong outer heliosheath ENA feature appears near the nose of the heliosphere. A weaker, complementary feature is also present consisting entirely of inner heliosheath ENAs. From this feature the direction of the interstellar magnetic field can be easily inferred.