NGTS and WASP photometric recovery of a single-transit candidate from TESS
NGTS and WASP photometric recovery of a single-transit candidate from TESS
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来自 TESS 的单凌日候选者的 NGTS 和 WASP 光度恢复
DOI：
10.1093/mnras/stz3212
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发表时间：
2019
影响因子：
4.8
通讯作者：
Gill S
中科院分区：
文献类型：
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作者：
Gill S
凌日系外行星巡天卫星（TESS）产生了大量的单凌事件候选者，因为使命监测大多数恒星只有2027天。这样的候选者对应于长周期行星或食双星。利用TESS Sector 1的全帧图像，我们在中等演化的F星星TIC-238855958（Tmag= 10.23，Teff = 6280 ± 85 K）周围发现了一个7750 ppm的单凌事件，持续时间为7 h。使用档案WASP测光，我们限制了真正的轨道周期的三个可能的值之一。我们用NGTS探测到了一个随后的凌日事件，它揭示了轨道周期为38.20 d。CORALIE摄谱仪的径向速度测量结果显示，次级天体的质量为M2 = 0.148 ± 0.003 M <$，表明该系统是一个F-M食双星。M矮星伴星的半径为R2 = 0.171 ± 0.003 R <$，使其成为该质量区域内最具特征的恒星之一。我们发现它的半径比恒星演化模型的预期值低2.3σ。
The Transiting Exoplanet Survey Satellite (TESS) produces a large number of single-transit event candidates, since the mission monitors most stars for only ∼27 d. Such candidates correspond to long-period planets or eclipsing binaries. Using theTESSSector 1 full-frame images, we identified a 7750 ppm single-transit event with a duration of 7 h around the moderately evolved F-dwarf star TIC-238855958 (Tmag= 10.23,Teff= 6280 ± 85 K). Using archival WASP photometry we constrained the true orbital period to one of three possible values. We detected a subsequent transit-event with NGTS, which revealed the orbital period to be 38.20 d. Radial velocity measurements from the CORALIE Spectrograph show the secondary object has a mass ofM2= 0.148 ± 0.003 M⊙, indicating this system is an F–M eclipsing binary. The radius of the M-dwarf companion isR2= 0.171 ± 0.003 R⊙, making this one of the most well characterized stars in this mass regime. We find that its radius is 2.3σ lower than expected from stellar evolution models.