论文标题
附近二进制星的天文标识II：附近恒星盖亚目录中的天文二进制
Astrometric identification of nearby binary stars II: Astrometric binaries in the Gaia Catalogue of Nearby Stars
论文作者
论文摘要
我们检查仅从天体偏差中识别二元系统的能力。我们将分析应用于Gaia EDR3和DR2数据，特别是附近恒星的Gaia目录。我们表明，我们必须在本地体积上重新归一化（R）UWE，以避免局部观察结果，从而给出局部单位重量误差（LUWE）。我们使用LUWE> 2的简单标准以及少量质量切割来清除可能的污染物，以识别未解决的二进制候选者。我们在100 pc的太阳（本卷中的10％不足10％）内确定了22,699名二进制候选者。我们发现，巨星的天体二进制候选分数约为20％，主序列为10％，白矮人的序列为1％。我们还通过计算光度变异性与天文噪声之间的相关性来寻找可变性引起的动摇，并表明VIM可能主导着亚极质量MS恒星的二元群体。我们讨论了仅从天体中识别非发光大型伴侣的可能性和局限性，但发现我们的方法对这些方法不敏感。最后，我们将MS二进制文件与纸张I的模拟样本进行比较，该样品表现出极好的一致性，并计算出绝对大小的函数的星体候选二元分数。
We examine the capacity to identify binary systems from astrometric deviations alone. We apply our analysis to the Gaia eDR3 and DR2 data, specifically the Gaia Catalogue of Nearby Stars. We show we must renormalize (R)UWE over the local volume to avoid biasing local observations, giving a Local Unit Weight Error (LUWE). We use the simple criterion of LUWE>2, along with a handful of quality cuts to remove likely contaminants, to identify unresolved binary candidates. We identify 22,699 binary candidates within 100 pc of the Sun (just under 10% of sources in this volume). We find an astrometric binary candidate fraction of around 20% for giant stars, 10% on the Main Sequence and lower than 1% for White Dwarfs. We also look for Variability Induced Movers, by computing the correlation between photometric variability and astrometric noise -- and show that VIMs may dominate the binary population of sub-Solar mass MS stars. We discuss the possibility and limitations of identifying non-luminous massive companions from astrometry alone, but find that our method is insensitive to these. Finally, we compare the astrometric deviations of MS binaries to the simulated sample from paper I, which show excellent agreement, and compute the astrometric candidate binary fraction as a function of absolute magnitude.
