Transiting exoplanets from the CoRoT space mission - II. CoRoT-Exo-2b: a transiting planet around an active G star
Transiting exoplanets from the CoRoT space mission - II. CoRoT-Exo-2b: a transiting planet around an active G star
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CoRoT 太空任务中的凌日系外行星 - II。
DOI：
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发表时间：
2008
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通讯作者：
G. Wuchterl
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作者：
R. Alonso;M. Auvergne;A. Baglin;M. Ollivier;C. Moutou;D. Rouan;H. Deeg;S. Aigrain;J. Almenara;M. Barbieri;P. Barge;W. Benz;P. Bord'e;F. Bouchy;R. Reza;M. Deleuil;R. Dvorak;A. Erikson;M. Fridlund;M. Gillon;P. Gondoin;T. Guillot;A. Hatzes;G. H'ebrard;P. Kabáth;L. Jorda;H. Lammer;A. L'eger;A. Llebaria;B. Loeillet;P. Magain;M. Mayor;T. Mazeh;M. Patzold;F. Pepe;F. Pont;D. Queloz;H. Rauer;Avi Shporer;J. Schneider;B. Stecklum;S. Udry;G. Wuchterl
上下文。CoRoT任务是从太空搜索系外行星的先驱，已经完成了对银河面上∼12000颗恒星的第一个150天的连续观测。对原始数据的分析确定了最有希望的候选人，并触发了基于地面的后续行动。目标。本文报道了周期为1.743天的凌日行星CoRoT-Exo-2b的发现，并对其主要参数进行了表征。方法：研究方法。我们对宇宙碰撞的CoRoT原始光曲线、轨道残留物和来自恒星的低频信号进行了滤波。对78个样机的折光曲线进行了模型拟合，得到了主要参数。结合Sophie、Coralie和HARPS光谱仪获得的径向速度数据对系统进行了表征。2.5min的位相折叠光曲线受行星对恒星活动区的成功掩星影响，出射部分的色散以通量为单位达到1.0 9×10−4。结果。得到该行星的半径为1.465±0.029 RJup，质量为3.31±0.16MJup，密度为1.31±0.04g/cm3。CoRoT-Exo-2b的大半径不能用现有的辐照行星演化模型来解释。
Context. The CoRoT mission, a pioneer in exoplanet searches from space, has completed its first 150 days of continuous observations of ∼12 000 stars in the galactic plane. An analysis of the raw data identifies the most promising candidates and triggers the ground-based follow-up. Aims. We report on the discovery of the transiting planet CoRoT-Exo-2b, with a period of 1.743 days, and characterize its main parameters. Methods. We filter the CoRoT raw light curve of cosmic impacts, orbital residuals, and low frequency signals from the star. The folded light curve of 78 transits is fitted to a model to obtain the main parameters. Radial velocity data obtained with the SOPHIE, CORALIE and HARPS spectrographs are combined to characterize the system. The 2.5 min binned phase-folded light curve is affected by the effect of sucessive occultations of stellar active regions by the planet, and the dispersion in the out of transit part reaches a level of 1.09 × 10 −4 in flux units. Results. We derive a radius for the planet of 1.465 ± 0.029 RJup and a mass of 3.31 ± 0.16 MJup, corresponding to a density of 1.31 ± 0.04 g/cm 3 . The large radius of CoRoT-Exo-2b cannot be explained by current models of evolution of irradiated planets.