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arXiv · 1408.5934

Lyman-alpha observations of astrospheres

Jeffrey L. Linsky·Brian E. Wood
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Abstract

Charge-exchange reactions between outflowing stellar wind protons and interstellar neutral hydrogen atoms entering a stellar astrosphere produce a region of piled-up-decelerated neutral hydrogen called the hydrogen wall. Absorption by this gas, which is observed in stellar Lyman-alpha emission lines, provides the only viable technique at this time for measuring the mass-loss rates of F-M dwarf stars. We describe this technique, present an alternative way for understanding the relation of mass-loss rate with X-ray emission, and identify several critical issues.

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Jeffrey L. Linsky, Brian E. Wood. 2014-08-25. Lyman-alpha observations of astrospheres. https://arxiv.org/abs/1408.5934

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