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Hydrogen wall and heliosheath Lyman-alpha absorption toward nearby stars: possible constraints on the heliospheric interface plasma flow

V. Izmodenov·B. Wood·R. Lallement
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Abstract

In this paper, we study heliospheric Ly-$α$ absorption toward nearby stars in different lines of sight. We use the Baranov-Malama model of the solar wind interaction with a two-component (charged component and H atoms) interstellar medium. Interstellar atoms are described kinetically in the model. The code allows us to separate the heliospheric absorption into two components, produced by H atoms originating in the hydrogen wall and heliosheath regions, respectively. We study the sensitivity of the heliospheric absorption to the assumed interstellar proton and H atom number densities. These theoretical results are compared with interstellar absorption toward six nearby stars observed by the Hubble Space Telescope.

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V. Izmodenov, B. Wood, R. Lallement. 2002-07-05. Hydrogen wall and heliosheath Lyman-alpha absorption toward nearby stars: possible constraints on the heliospheric interface plasma flow. https://doi.org/10.1029/2002ja009394

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