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arXiv 0801.1841astro-ph
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太阳系外凌日行星的改进参数

Improved parameters for extrasolar transiting planets

G. Torres, J. N. Winn, M. J. Holman

摘要:

我们提出了改进的过境系外行星的物理参数的值,基于自洽和统一的分析过境光变曲线和可观察到的主机恒星的属性。以前,由于在个别情况下应用的方法差异很大,因此很难解释凌日系外行星的整体性质。此外,以前的研究往往忽略了一个重要的约束,平均恒星密度,可以直接从光变曲线。本文的主要贡献是:(1)对所有已报道的主恒星有效温度和金属丰度值进行了严格的汇编和误差评估;(2)在建立凌日光变曲线模型中采用了一致的方法和误差处理; 3)基于恒星演化模型的恒星质量和半径的更精确估计,结合恒星密度的光度限制。我们使用我们的研究结果,重新审视一些以前提出的模式和相关性的合奏。我们证实了质量周期相关性,我们发现了一个新的模式内的分散这种相关性的证据:在一个给定的轨道周期,贫金属恒星周围的行星比富金属恒星周围的行星质量更大。同样地,我们根据行星的Safronov数确认了所提出的行星二分法,并且我们发现了证据表明,具有小Safronov数的系统平均更富含金属。最后,我们证实了导致高金属量恒星拥有更重元素含量的行星的建议的趋势。

英文摘要:

We present refined values for the physical parameters of transiting exoplanets, based on a self-consistent and uniform analysis of transit light curves and the observable properties of the host stars. Previously it has been difficult to interpret the ensemble properties of transiting exoplanets, because of the widely different methodologies that have been applied in individual cases. Furthermore, previous studies often ignored an important constraint on the mean stellar density that can be derived directly from the light curve. The main contributions of this work are 1) a critical compilation and error assessment of all reported values for the effective temperature and metallicity of the host stars; 2) the application of a consistent methodology and treatment of errors in modeling the transit light curves; and 3) more accurate estimates of the stellar mass and radius based on stellar evolution models, incorporating the photometric constraint on the stellar density. We use our results to revisit some previously proposed patterns and correlations within the ensemble. We confirm the mass-period correlation, and we find evidence for a new pattern within the scatter about this correlation: planets around metal-poor stars are more massive than those around metal-rich stars at a given orbital period. Likewise, we confirm the proposed dichotomy of planets according to their Safronov number, and we find evidence that the systems with small Safronov numbers are more metal-rich on average. Finally, we confirm the trend that led to the suggestion that higher-metallicity stars harbor planets with a greater heavy-element content.

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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