标题： 用多凌日系统模拟多个半径谷的形成机制 显示英文标题

标题： Modeling Multiple Radius Valley Emergence Mechanisms With Multi-Transiting Systems

摘要： 小于海王星的近距离行星形成两个不同的群体，由岩石超级地球和亚海王星组成，可能拥有原始的氢/氦包层。 分隔这两个行星群体的半径山谷的起源仍然是一个开放性问题，有观点认为它可能直接来自行星形成过程，或者通过后续的大气逃逸产生。 跨越半径山谷的多凌日系统已被证明是XUV驱动质量损失的有效诊断工具。 在此，我们将这一框架扩展到测试XUV驱动的光致蒸发、核心驱动的质量损失以及受吸积限制的原始半径山谷模型。 专注于多凌日系统使我们能够消除个体系统中不可观测的量，例如恒星XUV光度历史和原行星盘的特性。 我们在所有221个已知的多凌日系统上测试了每个提出的半径山谷出现机制，并计算了系统中包裹行星的最小质量，以符合模型。 我们将模型预测与75个具有测量质量的系统进行比较，发现大多数系统可以由三种提出的机制中的任意一种解释。 我们还检查了模型一致性作为恒星质量和恒星金属丰度的函数，但未发现显著趋势。 在多凌日系统能够作为半径山谷出现模型的有效诊断工具之前，需要更多具有质量特征的多凌日系统。 本文中提出的模型评估软件可在GitHub上获得，并可用于未来的多凌日系统发现。 显示英文摘要

摘要： Close-in planets smaller than Neptune form two distinct populations composed of rocky super-Earths and sub-Neptunes that may host primordial H/He envelopes. The origin of the radius valley separating these two planet populations remains an open question and has been posited to emerge either directly from the planet formation process or via subsequent atmospheric escape. Multi-transiting systems that span the radius valley are known to be useful diagnostics of XUV-driven mass loss. Here, we extend this framework to test XUV-driven photoevaporation, core-powered mass loss, and an accretion-limited primordial radius valley model. Focusing on multi-transiting systems allows us to eliminate unobservable quantities that are shared within individual systems such as stellar XUV luminosity histories and the properties of the protoplanetary disk. We test each proposed radius valley emergence mechanism on all 221 known multi-transiting systems and calculate the minimum masses of the systems' enveloped planets to be consistent with the models. We compare our model predictions to 75 systems with measured masses and find that the majority of systems can be explained by any of the three proposed mechanisms. We also examine model consistency as a function of stellar mass and stellar metallicity but find no significant trends. More multi-transiting systems with mass characterizations are required before multi-transiting systems can serve as a viable diagnostic of radius valley emergence models. Our software for the model evaluations presented herein is available on GitHub and may be applied to future multi-transiting system discoveries.