Variations of interstellar H atom parameters in the outer heliosphere: solar cycle effects

In this paper, we study response of the heliospheric plasma interface, the region of the solar wind interaction with the local interstellar medium, to 11-year solar cycle variations of the solar wind. We explore how the solar wind variations influence interstellar H atoms in the heliospheric interface, which are coupled to plasma by charge exchange. We develop the self-consistent model, where the kinetic equation for interstellar H atom velocity distribution function is solved self-consistently with the gas dynamic equations for the charged (electrons and protons) component. It is shown that the termination shock location varies within +/-7 AU, the heliopause variation is similar to2 AU, and the bow shock variation is negligible. The important new result is that at large heliocentric distances the density of the interstellar H atoms varies within similar to10% with solar cycle. The variation of density increases closer to the Sun up to 30% at 5 AU. (C) 2004 COSPAR. Published by Elsevier Ltd. All rights reserved.