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arXiv · 2106.04937

The winds of young Solar-type stars in the Hyades

Dag Evensberget·Bradley D. Carter·Stephen C. Marsden·Leigh Brookshaw·Colin P. Folsom
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Abstract

Stellar winds govern the spin-down of Solar-type stars as they age, and play an important role in determining planetary habitability, as powerful winds can lead to atmospheric erosion. We calculate three-dimensional stellar wind models for five young Solar-type stars in the Hyades cluster, using TOUPIES survey stellar magnetograms and state-of-the-art Alfv\'en wave driven wind modelling. The stars have the same 0.6-Gyr age and similar fundamental parameters, and we account for the uncertainty in and underestimation of absolute field strength inherent in Zeeman-Doppler imaging by adopting both unscaled and scaled (by a factor of five) field strengths. For the unscaled fields, the resulting stellar wind mass loss is 2-4 times greater and the angular momentum loss 2-10 times greater than for the Sun today, with the scaled results correspondingly greater. We compare our results with a range published of wind models and for the Alfv\'en wave driven modelling see evidence of mass loss saturation at about $10 \dot M_\odot$.

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Dag Evensberget, Bradley D. Carter, Stephen C. Marsden, Leigh Brookshaw, Colin P. Folsom. 2021-06-09. The winds of young Solar-type stars in the Hyades. https://doi.org/10.1093/mnras/stab1696

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