Instrumental data are affected by systematic effects that dominate the errors and can be relevant when searching for small signals. This is the case of the K2 mission, a follow up of the Kepler mission, that, after a failure on two reaction wheels, has lost its stability properties rising strongly the systematics in the light curves and reducing its photometric precision. In this work, we have developed a general method to remove time related systematics from a set of light curves, that has been applied to K2 data. The method uses the Principal Component Analysis to retrieve the correlation between the light curves due to the systematics and to remove its effect without knowing any information other than the data itself. We have applied the method to all the K2 campaigns available at the Mikulski Archive for Space Telescopes, and we have tested the effectiveness of the procedure and its capability in preserving the astrophysical signal on a few transits and on eclipsing binaries. One product of this work is the identification of stable sources along the ecliptic plane that can be used as photometric calibrators for the upcoming Atmospheric Remote-sensing Exoplanet Large-survey mission.

中文翻译：

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主成分分析纠正数据系统性。案例研究：K2 光变曲线

仪器数据受主导误差的系统效应的影响，并且在搜索小信号时可能是相关的。K2 任务就是这种情况，它是开普勒任务的后续行动，在两个反作用轮发生故障后，它失去了稳定性，光变曲线的系统性急剧上升并降低了其光度测量精度。在这项工作中，我们开发了一种从一组光曲线中去除时间相关系统性的通用方法，该方法已应用于 K2 数据。该方法使用主成分分析来检索由于系统学引起的光变曲线之间的相关性，并在不知道数据本身以外的任何信息的情况下消除其影响。我们已将该方法应用于 Mikulski Archive for Space Telescopes 中所有可用的 K2 活动，我们已经测试了该程序的有效性及其在一些凌日和食双星上保存天体物理信号的能力。这项工作的一项成果是沿黄道平面确定稳定源，可用作即将进行的大气遥感系外行星大型测量任务的光度校准器。