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arXiv · 1809.01109

Implications of Recent Stellar Wind Measurements

Brian E. Wood
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Abstract

Very recent measurements of stellar winds are used to update relations between winds and coronal activity. New wind constraints include an upper limit of Mdot<0.1 Mdot_sun for Tau Ceti (G8 V), derived from a nondetection of astrospheric H I Lyman-alpha absorption. This upper limit is reported here for the first time, and represents the weakest wind constrained using the astrospheric absorption technique. A high mass loss rate measurement of Mdot=10 Mdot_sun for Delta Pav (G8 IV) from astrospheric Lyman-alpha absorption suggests stronger winds for subgiants than for main sequence stars of equivalent activity. A very low mass-loss rate of Mdot~0.06 Mdot_sun recently estimated for GJ 436 (M3 V) from Lyman-alpha absorption from an evaporating exoplanetary atmosphere implies inactive M dwarfs may have weak winds compared with GK dwarfs of similar activity.

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Brian E. Wood. 2018-09-04. Implications of Recent Stellar Wind Measurements. https://doi.org/10.1088/1742-6596/1100/1/012028

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