论文标题
贝叶斯高级律师对成像行星种群水平偏心分布的影响
The Impact of Bayesian Hyperpriors on the Population-Level Eccentricity Distribution of Imaged Planets
论文作者
论文摘要
轨道偏心率直接追踪子伴侣的形成机理和动力学历史。在这里，我们研究了高度群体对直接成像的近代伴侣（棕色矮人和冷木星）的样本的人口级偏心率分布的影响，该样本从等级贝叶斯建模（HBM）中推断出来。我们发现，高位的选择可以对成像伴侣推断的种群偏心分布产生重大影响，随着样本量和轨道覆盖率减少到反映现有样品的值，这种效果变得越来越重要。我们重新分析了Bowler等人的5-100 AU范围内成像的巨型行星的当前观察样品。 （2020）并发现成像行星样品暗示的潜在偏心率分布与使用径向速度检测到的近距离球星的偏心率分布广泛一致。此外，我们的分析支持了这项研究的结论，即长期巨型行星和棕色矮人的偏心率分布有所不同，这表明它对选择性高位的选择是可靠的。我们在开源Python软件包EPOP！中发布了HBM和正向建模代码，并将其自由提供给社区。
Orbital eccentricities directly trace the formation mechanisms and dynamical histories of substellar companions. Here, we study the effect of hyperpriors on the population-level eccentricity distributions inferred for the sample of directly imaged substellar companions (brown dwarfs and cold Jupiters) from hierarchical Bayesian modeling (HBM). We find that the choice of hyperprior can have a significant impact on the population-level eccentricity distribution inferred for imaged companions, an effect that becomes more important as the sample size and orbital coverage decrease to values that mirror the existing sample. We reanalyse the current observational sample of imaged giant planets in the 5-100 AU range from Bowler et al. (2020) and find that the underlying eccentricity distribution implied by the imaged planet sample is broadly consistent with the eccentricity distribution for close-in exoplanets detected using radial velocities. Furthermore, our analysis supports the conclusion from that study that long-period giant planets and brown dwarf eccentricity distributions differ by showing that it is robust to the choice of hyperprior. We release our HBM and forward modeling code in an open-source Python package, ePop!, and make it freely available to the community.
