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arXiv 0708.0834astro-ph
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TrES-4:一颗极低密度的凌日热木星

TrES-4: A Transiting Hot Jupiter of Very Low Density

Georgi Mandushev, Francis T. O'Donovan, David Charbonneau, Guillermo Torres, David W. Latham, Gáspár Á. Bakos, Edward W. Dunham, Alessandro Sozzetti, José M. Fe… 展开作者

Georgi Mandushev, Francis T. O'Donovan, David Charbonneau, Guillermo Torres, David W. Latham, Gáspár Á. Bakos, Edward W. Dunham, Alessandro Sozzetti, José M. Fernández, Gilbert A. Esquerdo, Mark E. Everett, Timothy M. Brown, Markus Rabus, Juan A. Belmonte, Lynne A. Hillenbrand

摘要:

我们报告发现了TrES-4,这是一颗热木星,每3.55天经过恒星GSC 02620-00648。根据恒星的高分辨率光谱,我们估计恒星的有效温度为Teff = 6100 +/- 150 K,根据凌日的高精度z和B测光,我们将半长轴和恒星半径的比值限制为a/R = 6.03 +/- 0.13。我们将这些值与模型恒星等时线进行比较,以将恒星质量限制为M* = 1.22 +/- 0.17 Msun。基于这个估计和光度时间序列,我们将恒星半径限制为R* = 1.738 +/- 0.092 Rsun,行星半径限制为Rp = 1.674 +/- 0.094 RJup。我们模拟我们的径向速度数据假设一个圆形轨道,并找到一个行星质量为0.84 +/- 0.10兆焦耳。我们的径向速度观测排除了线平分线的变化,这将表明一个似是而非的检测结果的混合食双星系统。TrES-4是所有已知凌日行星中半径最大、密度最低的。它对目前的热行星物理结构模型提出了挑战,并表明这类系外行星成员之间的物理特性多样性尚未得到充分探索。

英文摘要:

We report the discovery of TrES-4, a hot Jupiter that transits the star GSC 02620-00648 every 3.55 days. From high-resolution spectroscopy of the star we estimate a stellar effective temperature of Teff = 6100 +/- 150 K, and from high-precision z and B photometry of the transit we constrain the ratio of the semi-major axis and the stellar radius to be a/R = 6.03 +/- 0.13. We compare these values to model stellar isochrones to constrain the stellar mass to be M* = 1.22 +/- 0.17 Msun. Based on this estimate and the photometric time series, we constrain the stellar radius to be R* = 1.738 +/- 0.092 Rsun and the planet radius to be Rp = 1.674 +/- 0.094 RJup. We model our radial-velocity data assuming a circular orbit and find a planetary mass of 0.84 +/- 0.10 MJup. Our radial-velocity observations rule out line-bisector variations that would indicate a specious detection resulting from a blend of an eclipsing binary system. TrES-4 has the largest radius and lowest density of any of the known transiting planets. It presents a challenge to current models of the physical structure of hot Jupiters, and indicates that the diversity of physical properties amongst the members of this class of exoplanets has yet to be fully explored.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

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