The sensitivity of ISN He density and flux at 1 au to the parameters of a global heliosphere model

Interstellar Neutral He observed at 1 au is a mixture of pristine neutral He and of He atoms originating from the outer heliosheath due to charge exchange between ISN He and the perturbed flow of interstellar plasma in the outer heliosheath. This latter component, referred to as the Warm Breeze or the secondary component of ISN He, is a sensitive tracer of the conditions outside the heliopause. However, to elucidate these conditions from available observations, the sensitivity of the signal to the physical state of interstellar material and interstellar magnetic field must be recognized. We study this signal sensitivity by modeling the ISN He signal observed by IBEX. The simulations use the Warm Breeze synthesis model (Bzowski et al. 2017, 2019) coupled with the global MHD-kinetic heliosphere model MS-FLUKSS (Heerikhuisen & Pogorelov 2010), which was successfully used to find the interstellar magnetic field based on IBEX Ribbon. We investigate modifications of IBEX signal simulated with selected interstellar parameters varied within reasonably expected limits We point out that the ISN He signal is sensitive to these variations to such an extent that these effects should be possible to identify in the available data.