A method for selecting M dwarfs with an increased likelihood of unresolved ultracool companionship
A method for selecting M dwarfs with an increased likelihood of unresolved ultracool companionship
复制标题
DOI：
10.1093/mnras/stw061
复制
发表时间：
2016-01
影响因子：
4.8
通讯作者：
N. Cook;D. Pinfield;F. Marocco;B. Burningham;H. Jones;J. Frith;J. Zhong;A. Luo;Z. Qi;P. Lucas;M. Gromadzki;A. Day-Jones;R. Kurtev;Y. X. Guo;Y. Wang;Y. Bai;Z. Yi;R. Smart
中科院分区：
文献类型：
--
作者：
N. Cook;D. Pinfield;F. Marocco;B. Burningham;H. Jones;J. Frith;J. Zhong;A. Luo;Z. Qi;P. Lucas;M. Gromadzki;A. Day-Jones;R. Kurtev;Y. X. Guo;Y. Wang;Y. Bai;Z. Yi;R. Smart
定位M矮星的超低温伴星对于约束低质量形成模型、测量亚恒星动力学质量和半径以及测试超低温演化模型都很重要。我们提出了一种优化的方法来识别可能有未解决的超冷伴星的M矮星。我们基于光学和近红外颜色以及减少固有运动，构建了来自WISE， 2MASS和SDSS的440,694个候选天体的目录。在严格的变红、光度和质量约束下，我们分离了36,898个M矮星的子样本，并通过比较具有相似光学/近红外颜色（选择它们对有效温度和金属丰度的敏感性）的M矮星来寻找可能的中红外M矮星+超冷矮星候选者。我们提出了1082个M矮星+超低温矮星候选者。通过模拟M矮星的超冷伴星，我们估计在我们的M矮星+超冷伴星候选者中，未解决的超冷伴星的发生率至少是我们整个M矮星目录中平均值的四倍。我们讨论了可能的污染和偏差，并根据我们的模拟预测了候选产品的产量。
Locating ultra-cool companions to M dwarfs is important for constraining low-mass formation models, the measurement of sub-stellar dynamical masses and radii, and for testing ultra-cool evolutionary models. We present an optimised method for identifying M dwarfs which may have unresolved ultra-cool companions. We construct a catalogue of 440,694 candidates, from WISE, 2MASS and SDSS, based on optical and near-infrared colours and reduced proper motion. With strict reddening, photometric and quality constraints we isolate a sub-sample of 36,898 M dwarfs and search for possible mid-infrared M dwarf + ultra-cool dwarf candidates by comparing M dwarfs which have similar optical/near-infrared colours (chosen for their sensitivity to effective temperature and metallicity). We present 1,082 M dwarf + ultra-cool dwarf candidates for follow-up. Using simulated ultra-cool dwarf companions to M dwarfs, we estimate that the occurrence of unresolved ultra-cool companions amongst our M dwarf + ultra-cool dwarf candidates should be at least four times the average for our full M dwarf catalogue. We discuss possible contamination and bias and predict yields of candidates based on our simulations.