Photometric surveys of open clusters have produced extensive measurements of rotation periods on Sun‐like stars of different ages. In particular, observations of intermediate age clusters, such as the Pleiades and M34, indicate a brief episode of rapid deceleration of stellar rotation at Rossby numbers between 0.1 and 0.3. I used those results to obtain new insights into the long‐term evolution of chromospheric activity on solar mass stars.

中文翻译：

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太阳质量恒星的Rossby数和色球活动

通过对开放星团的光度测量，可以对不同年龄的类太阳恒星的自转周期进行广泛的测量。特别是，对中年星团（如the宿星号和M34）的观测表明，在Rossby数介于0.1和0.3之间时，恒星旋转快速减速的短暂事件。我利用这些结果获得了对太阳质量恒星上色球活动长期演变的新见解。