标题： 类似太阳的开普勒恒星的小行星存在变异性 显示英文标题

标题： Variability of Kepler Solar-Like Stars Harboring Small Exoplanets

摘要： 我们研究了宜居带凌日时间尺度上大量具有光谱特征的开普勒系外行星宿主恒星的光变曲线变化。 这些恒星取自埃弗雷特等人（2013年）的研究，性质类似于太阳，每颗恒星至少拥有一颗半径为$\le$2.5\re 的系外行星（或候选者）。所考察的变率时间尺度对于围绕类似太阳恒星的宜居带行星来说是典型的。我们注意到，发现最小的系外行星（$\le$1.2\re ），其对应的凌日深度小于$\sim$0.18 毫磁，通常发生在最亮且光度最稳定的恒星上。因此，在$Kepler$观测中，这些探测非常罕见。 一些更亮且演化程度更高的恒星（次巨星），其中许多表现出较大的径向速度抖动，被发现是我们样本中最光度安静的类似太阳恒星，并且是最有可能发现小行星凌日的地方。 讨论了太阳作为类似太阳恒星的代理，以深入了解光度变化的性质和原因。结果显示，$Kepler's$宽波段可见光观测对由色球活动引起的变率不敏感，而这种活动可能存在于观测到的恒星中。 显示英文摘要

摘要： We examine Kepler light curve variability on habitable zone transit timescales for a large uniform sample of spectroscopically studied Kepler exoplanet host stars. The stars, taken from Everett et al. (2013) are solar-like in their properties and each harbors at least one exoplanet (or candidate) of radius $\le$2.5\re. The variability timescale examined is typical for habitable zone planets orbiting solar-like stars and we note that the discovery of the smallest exoplanets ($\le$1.2\re) with corresponding transit depths of less than $\sim$0.18 mmag, occur for the brightest, photometrically quietest stars. Thus, these detections are quite rare in $Kepler$ observations. Some brighter and more evolved stars (subgiants), the latter which often show large radial velocity jitter, are found to be among the photometrically quietest solar-like stars in our sample and the most likely small planet transit hunting grounds. The Sun is discussed as a solar-like star proxy to provide insights into the nature and cause of photometric variability. It is shown that $Kepler's$ broad, visible light observations are insensitive to variability caused by chromospheric activity that may be present in the observed stars.