Evidence for Unresolved Exoplanet-hosting Binaries in Gaia DR2
Evidence for Unresolved Exoplanet-hosting Binaries in Gaia DR2
复制标题
盖亚 DR2 中未解析的系外行星双星系统的证据
DOI：
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发表时间：
2018
期刊：
影响因子：
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通讯作者：
D. Evans
中科院分区：
文献类型：
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作者：
D. Evans
本文描述了在已知的凌日系外行星（TEP）系统中探测其他恒星源的努力，这些恒星源在盖亚数据发布2 （DR2）目录中尚未解决或几乎没有解决。在凌日行星系统的光度和光谱观测中，存在多颗未解恒星，会对行星半径、质量和大气条件的测量产生偏差。除了对单个行星系统的影响外，由于系统地低估了质量和半径，在已知系外行星样本中存在未解决的恒星，会影响我们对行星系统的整体理解。这项工作使用沿扫描方向的天体测量拟合优度（GOF_AL）和天体测量过量噪声作为低分辨率双星的指标。许多已知的系外行星主恒星样本中的近距离双星具有非常显著的GOF_AL和天体测量过量噪声值，例如WASP-20AB，其天体测量过量噪声显著为$4720\sigma$, GOF_AL=124。
This note describes an effort to detect additional stellar sources in known transiting exoplanet (TEP) systems, which are unresolved or barely resolved in the Gaia Data Release 2 (DR2) catalogue. The presence of multiple unresolved stars in photometric and spectroscopic observations of a transiting planetary system biases measurements of the planet's radius, mass, and atmospheric conditions. In addition to the effect on individual planetary systems, the presence of unresolved stars across the sample of known exoplanets biases our overall understanding of planetary systems, due to the systematic underestimation of both masses and radii. This work uses the Astrometric Goodness of Fit in the Along-Scan direction (GOF_AL) and the Astrometric Excess Noise as indicators of poorly-resolved binaries. Many known close binaries in the exoplanet host star sample have highly significant GOF_AL and Astrometric Excess Noise values, such as WASP-20AB with Astrometric Excess Noise significant at $4720\sigma$ and GOF_AL=124.