Disentangling the stellar inclination of transiting planetary systems: Fully analytic approach to the Rossiter?McLaughlin effect incorporating the stellar differential rotation
Disentangling the stellar inclination of transiting planetary systems: Fully analytic approach to the Rossiter?McLaughlin effect incorporating the stellar differential rotation
复制标题
解开凌日行星系统的恒星倾角：结合恒星差分自转的罗西特麦克劳林效应的全面分析方法
DOI：
10.1093/pasj/psab102
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发表时间：
2021
影响因子：
2.3
通讯作者：
Suto Yasushi
中科院分区：
文献类型：
--
作者：
Sasaki Shin;Suto Yasushi
Rossiter-McLaughlin（RM）效应已被广泛用于估计凌日行星系统的天空投影自旋轨道角λ。以前的大多数分析都假设宿主星是刚性旋转体，其中RM速度异常的幅度与v sini成正比。当考虑到它们的纬向差异自转时，就可以打破简并，分别确定主星星星的赤道自转速度v θ和倾角i θ。我们采用恒星差分自转的参数化模型，推导出了RM效应的全解析近似公式。对于那些表现出类似于太阳的差异旋转的恒星，相应的RM速度调制达到几个m s−1。我们的结论是，纬度差异旋转提供了一种方法来估计i，从而完整的自旋轨道角，从RM数据分析单独。
The Rossiter–McLaughlin (RM) effect has been widely used to estimate the sky-projected spin-orbit angle, λ, of transiting planetary systems. Most of the previous analysis assumes that the host stars are rigid rotators in which the amplitude of the RM velocity anomaly is proportional tov⋆sini⋆. When their latitudinal differential rotation is taken into account, one can break the degeneracy, and determine separately the equatorial rotation velocityv⋆and the inclinationi⋆of the host star. We derive a fully analytic approximate formula for the RM effect adopting a parametrized model for the stellar differential rotation. For those stars that exhibit a differential rotation similar to that of the Sun, the corresponding RM velocity modulation amounts to several m s−1. We conclude that the latitudinal differential rotation offers a method to estimatei⋆, and thus the full spin-orbit angle ψ, from the RM data analysis alone.