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.

中文翻译：

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M矮星的自转-活动关系：从K2到TESS和PLATO

研究晚型恒星的自转-活动关系对于加深我们对恒星发电机和角动量演化的理解至关重要。我们研究了 M 矮星与 K2 的旋转-活动关系，其中它的了解特别少。我们分析了 K2 视场中来自 Superblink 自行运动目录的所有明亮和附近 M 矮星的光变曲线。对于在长节奏模式下在活动 C0-C19 中观察到的 430 M 矮人样本，我们确定了旋转周期和丰富的活动诊断。我们基于光度活动指标对旋转-活动关系的研究证实了先前公布的活动水平在~10d 的旋转周期内的突然变化。我们超过三倍的样本增加了这一发现的统计显着性。