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arXiv · 2005.08688

The rotation-activity relation of M dwarfs: From K2 to TESS and PLATO

St. Raetz·B. Stelzer·A. Scholz
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Abstract

Studies of the rotation-activity relation of late-type stars are essential to enhance our understanding of stellar dynamos and angular momentum evolution. We study the rotation-activity relation with K2 for M dwarfs where it is especially poorly understood. We analyzed the light curves of all bright and nearby M dwarfs form the Superblink proper motion catalog that were in the K2 field of view. For a sample of 430 M dwarfs observed in campaigns C0-C19 in long cadence mode we determined the rotation period and a wealth of activity diagnostics. Our study of the rotation-activity relation based on photometric activity indicators confirmed the previously published abrupt change of the activity level at a rotation period of ~10d. Our more than three times larger sample increases the statistical significance of this finding.

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St. Raetz, B. Stelzer, A. Scholz. 2020-05-18. The rotation-activity relation of M dwarfs: From K2 to TESS and PLATO. https://doi.org/10.1002/asna.202013727

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