Weighing in on the masses of retired A stars with asteroseismology : K2 observations of the exoplanet-host star HD 212771
Weighing in on the masses of retired A stars with asteroseismology : K2 observations of the exoplanet-host star HD 212771
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用星震学衡量退役 A 星的质量：系外行星主星 HD 212771 的 K2 观测
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发表时间：
2017
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影响因子：
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通讯作者：
A. Vanderburg
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作者：
T. Campante;D. Veras;Thomas S. H. North;A. Miglio;T. Morel;J. Johnson;W. Chaplin;G. Davies;D. Huber;J. Kuszlewicz;M. Lund;B. Cooke;Y. Elsworth;T. Rodrigues;A. Vanderburg
基于多普勒的行星调查指出，具有恒星质量的巨型行星的出现频率越来越高。这类调查依赖于演化的恒星来获取中等质量恒星(所谓的退役A星)的样本，这些恒星比它们的主序祖先更容易受到多普勒观测的影响。然而，有人假设，这些调查的目标亚巨星和低亮度红巨星的质量--通常是通过光谱分析和等时线拟合得出的-可能被系统性地高估了。在这里，我们使用K2星震学对系外行星-宿主恒星HD 212771这一特殊情况下的这个假设进行了检验。基准星震质量($1.45^{+0.10}_{-0.09}\：\TEXT{M}_{\ODOT}$)显著高于发现论文中报告的值($1.15\pm0.08\：\TEXT{M}_{\ODOT}$)，后者已被用来告知恒星质量-行星发生关系。因此，这一结果并不支持上述假设。恒星质量对行星系统命运的影响是敏感的。基于所得到的星震质量，我们预测了在潮汐作用力和恒星质量损失的影响下，绕HD 212771运行的木星行星的主序后演化。
Doppler-based planet surveys point to an increasing occurrence rate of giant planets with stellar mass. Such surveys rely on evolved stars for a sample of intermediate-mass stars (so-called retired A stars), which are more amenable to Doppler observations than their main-sequence progenitors. However, it has been hypothesised that the masses of subgiant and low-luminosity red-giant stars targeted by these surveys --- typically derived from a combination of spectroscopy and isochrone fitting --- may be systematically overestimated. Here, we test this hypothesis for the particular case of the exoplanet-host star HD 212771 using K2 asteroseismology. The benchmark asteroseismic mass ($1.45^{+0.10}_{-0.09}\:\text{M}_{\odot}$) is significantly higher than the value reported in the discovery paper ($1.15\pm0.08\:\text{M}_{\odot}$), which has been used to inform the stellar mass-planet occurrence relation. This result, therefore, does not lend support to the above hypothesis. Implications for the fates of planetary systems are sensitively dependent on stellar mass. Based on the derived asteroseismic mass, we predict the post-main-sequence evolution of the Jovian planet orbiting HD 212771 under the effects of tidal forces and stellar mass loss.