The spin-orbit alignment of the transiting exoplanet WASP-3b from Rossiter-McLaughlin observations
The spin-orbit alignment of the transiting exoplanet WASP-3b from Rossiter-McLaughlin observations
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Rossiter-McLaughlin 观测中凌日系外行星 WASP-3b 的自旋轨道排列
DOI：
10.1111/j.1365-2966.2010.16576.x
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发表时间：
2010
影响因子：
4.8
通讯作者：
Simpson E
中科院分区：
文献类型：
--
作者：
Simpson E
我们对行星系统WASP-3的Rossiter-McLaughlin效应进行了观测。在凌日过程中，使用上普罗旺斯天文台1.93米望远镜上的索菲摄谱仪进行了径向速度测量。该效应的形状表明，恒星自转轴和行星轨道轴(λ)之间的天空投影角很小，并且与内部的零一致。WASP-3b加入了∼，其中三分之二的行星测量到的自转-轨道角排列良好，被认为经历了动态温和的迁移过程，如行星-圆盘相互作用。我们发现了一种系统效应，它导致所测得的恒星自转速度(v sin i=19.6+2.2−2.1 km S−1)比由谱线展宽得到的值(v sin i=13.4±1.5 km S−1)异常地高。这被认为是由于在提取数据和建立模型时所作的假设不一致造成的。使用了Hirano等人开发的模型。为了解决这个问题，我们发现v sin i与光谱展宽测量得到的值一致(v sin i=15.7+1.4−1.3 KM S−1)。
We present an observation of the Rossiter–McLaughlin effect for the planetary system WASP-3. Radial velocity measurements were made during transit using the SOPHIE spectrograph at the 1.93-m telescope at Haute-Provence Observatory. The shape of the effect shows that the sky-projected angle between the stellar rotation axis and planetary orbital axis (λ) is small and consistent with zero within. WASP-3b joins the∼ two-thirds of planets with measured spin–orbit angles that are well aligned and are thought to have undergone a dynamically gentle migration process such as planet–disc interactions. We find a systematic effect which leads to an anomalously high determination of the projected stellar rotational velocity (v sin i= 19.6+ 2.2− 2.1 km s− 1) compared to the value found from spectroscopic line broadening (v sin i= 13.4±1.5 km s− 1). This is thought to be caused by a discrepancy in the assumptions made in the extraction and modelling of the data. Using a model developed by Hirano et al. designed to address this issue, we find v sin i to be consistent with the value obtained from spectroscopic broadening measurements (v sin i= 15.7+ 1.4− 1.3 km s− 1).