AI 中文总结
本研究提出ExoMOD I正向模型，结合MultiNest拟合开普勒DR25数据，揭示开普勒单、多行星系统轨道周期分布的统计差异，约束AMD分布，得出FGK矮星平均行星数及凌星探测遗漏概率等结论。
AI 中文摘要
凌星观测仅能探测到轨道朝向对遥远观测者而言接近边侧的行星，这为潜在行星系统结构的多种解释留下了很大空间。本文对开普勒望远镜的凌星观测进行正向建模，以表征近距行星系统的轨道特性。我们对行星半径、质量和轨道周期的潜在分布作出合理选择，用角动量亏缺（AMD）参数化轨道激发，并采用精确方法考虑凌星探测情况。对开普勒DR25数据的拟合使用MultiNest完成。我们发现，开普勒单行星系统与多行星系统的轨道周期分布存在统计差异——这可能是开普勒观测基线的结果。当高多重度系统（m≥5）中的行星被赋予理想相关的周期比时，观测到的间隙复杂度分布可被重现，高多重度系统可能保留了其形成条件的痕迹。间隙复杂度指标还有助于约束AMD分布。我们发现，具有正半径单调性的系统通常拥有更小的行星，这符合半径单调性受未探测天体影响的预期。开普勒视场中的一颗FGK型矮星平均应拥有约2.4±0.2颗行星，其行星半径范围为0.5<R_pl/R_⊕<7，轨道周期范围为3<P_orb<300天。对于一个已探测到的行星系统，开普勒凌星观测约有50%的概率遗漏至少一颗内行星或中等周期行星。
英文摘要
Transit observations only detect planets with favorable, near edge-on orientation of orbits as seen by a distant observer, which leaves much freedom for various interpretations in terms of the underlying planetary system architecture. Here we forward model transit observations of the Kepler telescope to characterize the orbital properties of close-in planetary systems. We make sensible choices about the underlying distributions of planet radii, masses and orbital periods, parameterize the orbital excitation with the Angular Momentum Deficit (AMD), and adopt an accurate method to account for transit detection. The fits to Kepler's DR25 data are executed with {\tt MultiNest}. We find that the orbital period distributions of Kepler singles and multis are statistically different from each other -- possibly a consequence of Kepler's observational baseline. The observed gap complexity distribution is reproduced when planets in high multiplicity systems ($m \geq 5$) are assigned ideally correlated period ratios. The high-multiplicity systems probably retained a memory of their formation conditions. The gap complexity metric also helps to constrain the AMD distribution. We find that systems with positive radius monotonicities typically harbor smaller planets, as expected if the radius monotonicity is influenced by non-detections. A FGK dwarf in the Kepler field should host $\simeq 2.4 \pm 0.2$ planets on average with radii $0.5 < R_{\rm pl}/R_\oplus < 7$ and orbital periods $3<P_{\rm orb}<300$ d. For a detected planetary system, there is roughly a 50\% chance that Kepler transit observations missed at least one inner or intermediate-period planet.
CommentsApJ, in press
