Open AccessHydrogen wall and heliosheath Ly α absorption toward nearby stars: Possible constraints on the heliospheric interface plasma flow
Author(s) -
Izmodenov Vlad,
Wood Brian E.,
Lallement Rosine
Publication year - 2002
Publication title -
journal of geophysical research: space physics
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.67
H-Index - 298
eISSN - 2156-2202
pISSN - 0148-0227
DOI - 10.1029/2002ja009394
Subject(s) - physics , heliosphere , interstellar medium , absorption (acoustics) , stars , plasma , astrophysics , energetic neutral atom , solar wind , hydrogen , astronomy , galaxy , nuclear physics , optics , quantum mechanics
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 (HST).