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arXiv · 2510.21456

Surface activity of a Rossby sequence of cool Hyades stars

K. G. Strassmeier·I. Ilyin·M. Steffen·S. A. Barnes
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Abstract

Aims. The Hyades cluster is key for the study of rotational, activity, and chemical evolution of solar-like low-mass stars. Here we present quantitative surface-activity information for a sequence of 21 Hyades dwarf stars. Conclusions. We conclude that the Rossby-number dependencies of the surface activity tracers A(Li), R(IRT), and B on our Hyades dwarf sequence primarily originate from convective motions, expressed by its turnover time, and only to a smaller and sometimes inverse extent from surface rotation and its related extra mixing.

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K. G. Strassmeier, I. Ilyin, M. Steffen, S. A. Barnes. 2025-10-24. Surface activity of a Rossby sequence of cool Hyades stars. https://doi.org/10.1051/0004-6361%2F202556888

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