文章基本信息

标题：California-Kepler Survey. IX. Revisiting the Minimum-mass Extrasolar Nebula with Precise Stellar Parameters
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作者：Fei Dai ; Joshua N.Winn ; Kevin Schlaufman 等
期刊名称：The Astronomical journal
印刷版ISSN：0004-6256
电子版ISSN：1538-3881
出版年度：2020
卷号：159
期号：6
页码：3397-3412
DOI：10.3847/1538-3881/ab88b8
语种：English
出版社：American Institute of Physics
摘要：We investigate a possible correlation between the solid surface density Σ of the minimum-mass extrasolar nebula (MMEN) and the host star mass Msstarf and metallicity [Fe/H].Leveraging on the precise host star properties from the California-Kepler Survey (CKS), we found that ${\rm{\Sigma }}={50}_{-20}^{+33}\,{\rm{g}}\,{\mathrm{cm}}^{-2}$ (a/1 au)−1.75±0.07 (Msstarf/M⊙)1.04±0.22 100.22±0.05[Fe/H] for Kepler-like systems (1–4R⊕; a < 1 au).The strong Msstarf dependence is reminiscent of previous dust continuum results that the solid disk mass scales with Msstarf.The weaker [Fe/H] dependence shows that sub-Neptune planets, unlike giant planets, form readily in lower metallicity environment.The innermost region (a < 0.1 au) of an MMEN maintains a smooth profile despite a steep decline of planet occurrence rate: a result that favors the truncation of disks by corotating magnetospheres with a range of rotation periods, rather than the sublimation of dust.The Σ of Kepler multitransiting systems shows a much stronger correlation with Msstarf and [Fe/H] than singles.This suggests that the dynamically hot evolution that produced single systems also partially removed the memory of formation in disks.Radial-velocity planets yielded a MMEN very similar to CKS planets; transit-timing-variation planets' postulated convergent migration history is supported by their poorly constrained MMEN.We found that lower mass stars have a higher efficiency of forming/retaining planets: for Sun-like stars, about 20% of the solid mass within ~1 au are converted/preserved as sub-Neptunes, compared to 70% for late-K to early-M stars.This may be due to the lower binary fraction, lower giant-planet occurrence, or the longer disk lifetime of lower mass stars.
关键词：Exoplanet;formation