Back to Volume
Paper: Kinetic Modeling of Neutral Atom Transport in the Heliosphere
Volume: 406, Numerical Modeling of Space Plasma Flows: ASTRONUM - 2008
Page: 189
Authors: Heerikhuisen, J.; Pogorelov, N.V.; Florinski, V.; Zank, G.P.; Kharchenko, V.
Abstract: The heliosphere is a bubble of solar-wind plasma inside the local interstellar cloud that is stretched by the relative motion of the Sun through the cloud. Although the solar-wind is almost completely ionized, the partially ionized interstellar medium provides a significant source of neutral atoms (especially Hydrogen) some of which cross the heliopause and interact with the solar wind. The interaction is complicated by the large collisional mean free paths (of the size of the heliosphere) and by the nature of the collisions that results in a collisionless ensemble of atoms which couple to the ionized component through charge-exchange. Thus, to model the H-atom distribution correctly, we need to employ a kinetic approach.

In this paper we introduce the solar-wind/interstellar-medium interaction problem and emphasize the importance of neutral atoms in shaping the heliosphere. We then present a Monte-Carlo method for kinetic modeling which couples the plasma and neutral populations through charge-exchange. The role of the differential cross-section in H-p collisions will also be discussed, and finally we highlight the importance this type of modeling for NASA’s IBEX mission.

Back to Volume