New Models of the Cosmic Dawn

宇宙黎明，当恒星第一次照亮宇宙时，是天文学中最令人兴奋的前沿之一。这些第一代的发光天体可能与附近的星系有很大的不同。虽然它们距离我们遥远，迄今为止望远镜无法观测到它们，但新的设施正在建设中，有望在未来几年内探测到这些第一代天体。该项目将开发并公开发布这些天体的新理论模型，该模型将把它们许多新观察到的特性联系在一个符合现代统计分析的连贯框架中。PI还将开发各种在线材料，向公众描述这个时代迷人的天体物理学，包括动画，教程和基于他的一些模型的可下载应用程序。这个项目将通过几个相关的努力推进我们对宇宙黎明号的了解。首先，PI将开发一套新的“半解析”星系形成模型，将其调整到我们宇宙历史上正常星系形成的最早阶段。这些模型将使用物理驱动的恒星形成和反馈处方来探索可能与这个时代相关的广泛的天体物理学。其次，他将改进再电离时代快速模拟中光子吸收的处理，这对于准确模拟该过程至关重要。最后，他将使用参数推理代码将这些新的理论模型与广泛的观测结果联系起来，包括星系测量和对再电离过程的低频无线电调查。该奖项反映了美国国家科学基金会的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

The Cosmic Dawn, when stars first illuminated the Universe, is one of the most exciting frontiers in astronomy. These first generations of luminous objects likely differed significantly from nearby galaxies. While their vast distance from us has so far prevented telescopes from observing them, new facilities are now under construction that hope to probe these first generations of objects in the next several years. This project will develop and publicly release a new theoretical model of these objects, which will link many of their newly observable properties in a coherent framework amenable to modern statistical analyses. The PI will also develop a variety of online materials describing the fascinating astrophysics of this era to the public, including animations, tutorials, and a downloadable application based on some of his models.This project will advance our understanding of the Cosmic Dawn through several related efforts. First, the PI will develop a new set of "semi-analytic" galaxy formation models tuned to the earliest phases of normal galaxy formation in our Universe's history. The models will use physically motivated star formation and feedback prescriptions to explore the wide range of astrophysics that may be relevant during this era. Second, he will improve the treatment of photon absorption in fast simulations of the reionization era, which is essential to model that process accurately. Finally, he will connect these new theoretical models to a wide range of observables, including galaxy measurements and low-frequency radio investigations of the reionization process, using a parameter inference code.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.