论文标题
trappist-1系统中自旋轨道对齐的证据
Evidence for Spin-orbit Alignment in the TRAPPIST-1 System
论文作者
论文摘要
为了衡量Trappist-1系统的Rossiter-mclaughlin效应，我们在行星E，F和B的转移过程中进行了高分辨率光谱。使用Subaru 8.2 m望远镜上的红外多普勒光谱仪获得光谱，并用Las Cumbres天主线全球望远镜的1 m望远镜获得的同时获得光度法。通过分析异常的径向速度，我们发现预计的恒星斜率为$λ= 1 \ pm 28 $度，假设这三个行星具有共辉晶轨道，尽管我们警告说径向速度数据显示出未知来源的噪声相关。我们还寻求证据表明恒星吸收线的预期变形，从而发现了B Planet B的“多普勒阴影”，错误警报概率为$ 1.7 \，\％$。对所观察到的残差互相关图的联合分析包括$λ= 19 _ { - 15}^{+13} $度。这些结果表明，尽管鼓励进一步的观察结果来验证这一结论，但Trappist-1恒星与行星的共同轨道平面并未完全不对。
In an effort to measure the Rossiter-McLaughlin effect for the TRAPPIST-1 system, we performed high-resolution spectroscopy during transits of planets e, f, and b. The spectra were obtained with the InfraRed Doppler spectrograph on the Subaru 8.2-m telescope, and were supplemented with simultaneous photometry obtained with a 1-m telescope of the Las Cumbres Observatory Global Telescope. By analyzing the anomalous radial velocities, we found the projected stellar obliquity to be $λ=1\pm 28$ degrees under the assumption that the three planets have coplanar orbits, although we caution that the radial-velocity data show correlated noise of unknown origin. We also sought evidence for the expected deformations of the stellar absorption lines, and thereby detected the "Doppler shadow" of planet b with a false alarm probability of $1.7\,\%$. The joint analysis of the observed residual cross-correlation map including the three transits gave $λ=19_{-15}^{+13}$ degrees. These results indicate that the the TRAPPIST-1 star is not strongly misaligned with the common orbital plane of the planets, although further observations are encouraged to verify this conclusion.
