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arXiv · 2012.10868

Nonlinear Alfv\'en Wave Model of Stellar Coronae and Winds from the Sun to M dwarfs

Takahito Sakaue·Kazunari Shibata
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Abstract

M dwarf's atmosphere and wind is expected to be highly magnetized. The nonlinear propagation of Alfv\'en wave could play a key role in both heating the stellar atmosphere and driving the stellar wind. Along this Alfv\'en wave scenario, we carried out the one-dimensional compressive magnetohydrodynamic (MHD) simulation about the nonlinear propagation of Alfv\'en wave from the M dwarf's photosphere, chromosphere to the corona and interplanetary space. Based on the simulation results, we develop the semi-empirical method describing the solar and M dwarf's coronal temperature, stellar wind velocity, and wind's mass loss rate. We find that M dwarfs' coronae tend to be cooler than solar corona, and that M dwarfs' stellar winds would be characterized with faster velocity and much smaller mass loss rate compared to those of the solar wind.

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Takahito Sakaue, Kazunari Shibata. 2020-12-20. Nonlinear Alfv\'en Wave Model of Stellar Coronae and Winds from the Sun to M dwarfs. https://doi.org/10.3847/2041-8213%2Fabd3a9

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