论文标题
热木星系外行星XO-6B的苔丝观察：没有过境时序变化的证据
TESS Observations of the Hot Jupiter Exoplanet XO-6b: No Evidence of Transit Timing Variations
论文作者
论文摘要
从以前的基于地面的观测值中，据报道，热木星系外行星XO-6B表现出明显周期性的过境时序变化（TTV），半振幅为14分钟，大约450天。这些变化被解释为是由于XO-6B和迄今未知的低质量行星之间的共振扰动引起的。为了更好地了解这个神秘的行星系统，我们分析了从过渡性系外行星调查卫星（TESS）中分析了三个数据扇区，该数据范围超过了七个月，该卫星（TESS）产生了高质量的光曲线，这些曲线非常适合表征外部球星和寻找TTVS。在这里，我们提出了3.7649893 $ \ pm $ 0.0000037天的更新轨道周期和2456652.7157 $ \ pm $ 0.0022 bjd $ _ {tdb} $。我们报告的行星参数虽然与它们的发现值一致，却大大提高了精度。值得注意的是，我们没有发现TTV的证据：我们可以在3 $σ$级别上排除TTVS $ \ gtrsim $ 2.5分钟。因此，苔丝数据具有足够的精度和时间基线，可以轻松揭示先前报道的TTV约10分钟。我们的发现突出了Tess的强大后续作品能力，并确认在热木星中很少见到TTV，与小星球的情况不同。
From previous ground-based observations, the hot Jupiter exoplanet XO-6b was reported to exhibit apparently periodic transit timing variations (TTVs), with a semi-amplitude of 14 minutes and a period of about 450 days. These variations were interpreted as being due to a resonant perturbation between XO-6b and a hitherto unknown low-mass planet orbiting the same star. To understand this enigmatic planetary system better, we analysed three sectors of data, spanning over seven months, from the Transiting Exoplanet Survey Satellite (TESS), which produces high-quality light curves that are well suited to characterizing exoplanets and searching for TTVs. Here we present an updated orbital period of 3.7649893 $\pm$ 0.0000037 days and a transit epoch of 2456652.7157 $\pm$ 0.0022 BJD$_{TDB}$. The planetary parameters we report, while consistent with their discovery values, have greatly improved precision. Notably, we find no evidence for TTVs: we can rule out TTVs $\gtrsim$ 2.5 minutes at the 3$σ$ level. Therefore, the TESS data have sufficient precision and time baseline to reveal readily the previously reported TTVs of approximately 10 minutes. Our findings highlight TESS's capabilities for robust follow-up, and confirm that TTVs are rarely seen in hot Jupiters, unlike is the case with small planets.
