Systematic analysis of stellar transit light curves for the characterization of short-period extrasolar planets

迄今为止，已经发现了3500多颗系外行星。对大量不同种类的行星系统的研究可以得出行星系统的形成和演化以及相关的物理过程的结论。凌日法是发现系外行星最成功的方法。像CoRoT、开普勒和K2这样的太空望远镜同时连续地观测了大量的恒星。轨道周期；通过拟合解析光曲线模型，从凌日观测得到行星半径、行星半长轴相对于恒星半径、行星轨道倾角和偏心率。行星质量是通过凌日和地面径向速度测量（RV）的组合来确定的，或者在某些情况下通过凌日时间变化（TTV）来确定。行星系统的其他物理性质偶尔也会在光曲线中被发现（例如，行星反射的光、椭球体的变化、恒星的微分旋转、恒星旋转轴与行星轨道之间的夹角、行星轨道的偏心率）。只有粗略的估计存在于其他属性（例如，附差、卫星、环和特洛伊）。该项目将系统地检查开普勒、CoRoT和K2任务中所有现有的行星凌日光曲线，以了解凌日之前、期间和之后已知的和/或理论上预测的变化。光曲线的大集合也可以为统计分析奠定基础，统计分析将描述以前无法解释的光曲线变化，然后描述相关的物理现象。我们希望运用我们在CoRoT、开普勒和K2太空任务中对恒星光曲线和行星凌日的分析中获得的丰富经验。我们的检测管道已经处理的数据将被更详细地利用。建立一种新的光曲线数值模型。该数值模型应能够模拟常用的曼德尔-阿戈尔模型中未考虑的光曲线现象。该模型应给出估计，如果某些现象可以检测到的光曲线与今天的技术，哪一种恒星可能适合观测（周期，恒星的光谱类型等）。该模型应有助于阐明未知现象的物理原因。对光曲线的系统研究应该增加直接从光曲线中获得的信息和参数的数量。另外，应使用信息用于识别误报。

More than 3500 extrasolar planets were discovered to date. The study of a large ensemble of planetary systems of different kind may allow to conclude on the formation and evolution of planetary systems and the associated physical processes. The transit method is the most successful method for the discovery of exoplanets. Space telescopes like CoRoT, Kepler and K2 observed a large number of stars simultaneously and continuously. The orbital period; the planetary radius and the planetary semi major axis relative to the radius of the star, the inclination and eccentricity of the planetary orbit are determined from the transit by fitting analytic light curve models. The planetary mass is determined from a combination of transit and ground-based radial velocity measurements (RV) or in some cases by transit time variation (TTV). Other physical properties of planetary systems were occasionally discovered in light curves (e.g. light reflected by planets, ellipsoid variation, differential rotation of the star, angle between the stellar rotation axis and the planetary orbit, eccentricity of planetary orbits). Only crude estimates exist for other properties (e.g., apsidal precession, moons, rings, and trojans). This project shall systematically examine all existing light curves with planetary transits from the Kepler, CoRoT and K2 missions for known and/or theoretically predicted variations before, during and after the transit. The large ensemble of light curves may also build the foundation for a statistical analysis which shall characterize previously unexplained variations in the light curves which may then describe the associated physical phenomena.We want to apply our extensive experience gained from the analysis of stellar light curves and planetary transits made on the space missions CoRoT, Kepler and K2. The data already processed with our detection pipeline shall be exploited in more detail. A new numerical light curve model shall be developed. This numerical model shall be able to simulate light curve phenomena not considered in the commonly used Mandel-Agol model. The model shall give estimates if certain phenomena are detectable in the light curves with today's technique and which kind of stars may be suitable for observation (period, spectral type of star, etc.). The model shall help to clarify the physical reason of unknown phenomena. The systematic investigation of the light curves should increase the information and the number of parameters obtained directly from the light curve. In addition, the information shall be used to identify false positives.