Many stars show activity cycles like the Sun. Kepler has gathered ∼200,000 light curves. Most of the Kepler stars only have long-cadence light curves, which limits their applicable methods. Some metrics, for example $S_{ph}$, are effective for long-cadence light curves but require rotation periods. In order to improve the utilization of Kepler light curves, we introduce and use the smoothness metric. The smoothness metric is able to analyze stars without a measured rotation period and is applicable for long-cadence light curves. We test and validate our metric, resulting in the detection of the 11 years solar cycle and a 457 days cycle for our prototype star KIC 9017220. We analyze 92,084 Kepler long-cadence light curves, and as our main results, we detect 4455 magnetic activity cycle candidates, but about 20 percent are false cycles and 50 percent are lower limits of the real cycles, and we analyze their causes in detail. As an investigation into the performance of our method, we simulate disturbance factors and prove that the p-value test is invalid under certain circumstances.

中文翻译：

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使用开普勒长节奏光曲线构建活动周期目录的尝试

许多恒星像太阳一样显示出活动周期。开普勒已经收集了约 200,000 条光曲线。大多数开普勒星只有长节奏的光变曲线，这限制了它们的适用方法。一些指标，例如${\mathrm{小号}}_{pH}$, 对长节奏光曲线有效，但需要旋转周期。为了提高开普勒光曲线的利用率，我们引入并使用了平滑度度量。平滑度度量能够在没有测量自转周期的情况下分析恒星，适用于长节奏光变曲线。我们测试并验证了我们的度量标准，从而检测到我们的原型恒星 KIC 9017220 的 11 年太阳周期和 457 天周期。我们分析了 92,084 条开普勒长周期光曲线，作为我们的主要结果，我们检测到 4455 次磁活动周期候选，但大约 20% 是错误周期，50% 是真实周期的下限，我们详细分析了它们的原因。作为对我们方法性能的调查，我们模拟干扰因素并证明p-value 测试在某些情况下无效。