The Gaia–Kepler Stellar Properties Catalog. II. Planet Radius Demographics as a Function of Stellar Mass and Age
The Gaia–Kepler Stellar Properties Catalog. II. Planet Radius Demographics as a Function of Stellar Mass and Age
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DOI：
10.3847/1538-3881/aba18a
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发表时间：
2020-05
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影响因子：
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通讯作者：
T. Berger;D. Huber;E. Gaidos;J. V. van Saders;L. Weiss
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文献类型：
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作者：
T. Berger;D. Huber;E. Gaidos;J. V. van Saders;L. Weiss
对系外行星人口统计的研究需要大样本和对系外行星宿主恒星的精确限制。使用Berger等人使用Gaia Data Release 2导出的均匀开普勒恒星属性，我们重新计算了开普勒行星半径和入射通量，并研究了它们随恒星质量和年龄的分布。我们测量的行星半径谷的恒星质量的依赖性是/ =，与行星质量依赖于恒星质量（0.24-0.35）和核心动力质量损失（0.33）预测的斜率一致。我们还发现了跨越半径谷的行星人口的恒星年龄依赖的第一个证据。具体来说，我们确定超级地球（1-1.8）到次海王星（1.8-3.5）的比例在年轻时（1 Gyr）从0.61 ± 0.09增加，与核心动力质量损失的预测一致，即形成半径谷的机制在Gyr时间尺度上运行。此外，我们发现一个试探性的半径相对较冷（FP 650），并表明这些行星优先轨道更发达的恒星相比，其他行星在类似的入射通量。此外，我们还确定了冷（Fp < 20）膨胀行星的候选者，提出了一个修订后的可居住区候选者列表，并发现单个和多个凌日行星系统的年龄在统计上是不可区分的。
Studies of exoplanet demographics require large samples and precise constraints on exoplanet host stars. Using the homogeneous Kepler stellar properties derived using the Gaia Data Release 2 by Berger et al., we recompute Kepler planet radii and incident fluxes and investigate their distributions with stellar mass and age. We measure the stellar mass dependence of the planet radius valley to be / = , consistent with the slope predicted by a planet mass dependence on stellar mass (0.24–0.35) and core-powered mass loss (0.33). We also find the first evidence of a stellar age dependence of the planet populations straddling the radius valley. Specifically, we determine that the fraction of super-Earths (1–1.8 ) to sub-Neptunes (1.8–3.5 ) increases from 0.61 ± 0.09 at young ages (1 Gyr), consistent with the prediction by core-powered mass loss that the mechanism shaping the radius valley operates over Gyr timescales. Additionally, we find a tentative decrease in the radii of relatively cool (Fp 650 ) and show that these planets are preferentially orbiting more evolved stars compared to other planets at similar incident fluxes. In addition, we identify candidates for cool (Fp < 20 ) inflated Jupiters, present a revised list of habitable zone candidates, and find that the ages of single and multiple transiting planet systems are statistically indistinguishable.