Doppler search for exoplanet candidates and binary stars in a CoRoT field using a multi-fiber spectrograph - I. Global analysis and first results
Doppler search for exoplanet candidates and binary stars in a CoRoT field using a multi-fiber spectrograph - I. Global analysis and first results
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使用多光纤摄谱仪在 CoRoT 场中进行多普勒搜索系外行星候选者和双星 - I. 全局分析和初步结果
DOI：
10.1051/0004-6361:20077176
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发表时间：
2007
影响因子：
6.5
通讯作者：
Nuno C. Santos
中科院分区：
文献类型：
--
作者：
B. Loeillet;F. Bouchy;F. Bouchy;M. Deleuil;F. Royer;J. Bouret;C. Moutou;P. Barge;P. Laverny;F. Pont;A. Recio;N. Santos;Nuno C. Santos
上下文短周期巨型系外行星群的发现，即所谓的热木星群，以及它们与褐矮星和低质量恒星的联系，挑战了行星形成和演化的传统观点。目标。我们利用多光纤设施GIRAFFE和UVES/FLAMES（VLT）进行了第一次大型径向速度调查，使用多光纤摄谱仪探测行星，棕矮星候选者和双星。方法.我们在连续5个半夜中观测了816颗恒星。这些恒星是在空间使命CoRoT的一个系外行星区域内选择的。结果我们计算了这些恒星的径向速度，并表明，一个系统的误差地板达到30 m s-1超过5个连续的夜晚与GIRAFFE仪器。在整个样本中，多普勒测量使我们能够识别出50个双星样本，9个活跃或混合双星，5个未解决的案例，14个系外行星和棕矮星候选者。现在需要进一步更高精度的多普勒测量来确认和更好地表征这些候选者。结论.这项研究证明了多光纤方法在寻找系外行星以及跟踪过境系外行星候选者方面进行大型径向速度调查的效率。大量恒星群的光谱特性是CoRoT空间使命等任务的一个有趣的副产品。
Context. The discovery of the short-period giant exoplanet population, the so-called hot Jupiter population, and their link to brown dwarfs and low-mass stars challenges the conventional view of planet formation and evolution. Aims. We took advantage of the multi-fiber facilities GIRAFFE and UVES/FLAMES (VLT) to perform the first large radial velocity survey using a multi-fiber spectrograph to detect planetary, brown-dwarf candidates and binary stars. Methods. We observed 816 stars during 5 consecutive half-nights. These stars were selected within one of the exoplanet fields of the space mission CoRoT. Results. We computed the radial velocities of these stars and showed that a systematic error floor of 30 m s -1 was reached over 5 consecutive nights with the GIRAFFE instrument. Over the whole sample the Doppler measurements allowed us to identify a sample of 50 binaries, 9 active or blended binary stars, 5 unsolved cases, 14 exoplanets and brown-dwarf candidates. Further higher precision Doppler measurements are now necessary to confirm and better characterize these candidates. Conclusions. This study demonstrates the efficiency of a multi-fiber approach for large radial-velocity surveys in search for exoplanets as well as the follow-up of transiting exoplanet candidates. The spectroscopic characterization of the large stellar population is an interesting by-product of such missions as the CoRoT space mission.