The Formation of the First Galaxies and their Connection to the Present Day

ast -1211626在宇宙再电离过程中，智慧矮星系提供了大部分电离光子，事实上，最近的观测已经开始揭示这样的星系。为了理解这些并计划未来的观测，有必要且及时地构建高红移星系的现实模型。该项目将开展宇宙学自适应网格细化辐射流体动力学模拟，重点关注第一个星系的形成及其在不同大尺度环境下的演变。这些模拟包括辐射和超新星反馈，向星族II恒星形成的自一致过渡，以及通过辐射压力对恒星形成的自我调节。他们将解析分子云和恒星关联，并使用自适应耦合射线追踪精确计算辐射输运。目前对高红移星系和附近矮星系的观测将有助于限制物理模型。为了与附近的矮星系建立直接联系，模拟将嵌入到一个更大的体积中，以跟踪矮星系的演化到今天，并预测它们的起源以及与早期宇宙的联系。参与的初级研究人员将获得宇宙学和天体物理学、数值算法、高性能计算和软件工程等广泛问题的专业知识。也将有机会解决从大型多维计算机模拟中可视化结果的挑战性问题。首席研究员将继续将研究活动整合到K-12学校和其他公共场所的教学中，以及通过在线学习环境。

AST-1211626WiseDwarf galaxies provided the majority of the ionizing photon budget during cosmic reionization, and in fact recent observations have begun to reveal such galaxies. To understand these and planned future observations, it is necessary, and timely, to construct realistic models of high-redshift galaxies. This project will carry out cosmological adaptive mesh refinement radiation hydrodynamics simulations that focus on the formation of the first galaxies and their evolution to the present-day in varying large-scale environments. These simulations include radiative and supernova feedback, a self-consistent transition to Population II star formation, and self-regulation of star formation through radiation pressure. They will resolve molecular clouds and stellar associations, and compute radiation transport accurately using adaptive coupled ray tracing. Current observations of high-redshift galaxies and nearby dwarf galaxies will help to constrain the physical model. To make a direct connection to nearby dwarf galaxies, simulations will be embedded in a larger volume to follow dwarf galaxy evolution to the present-day and make predictions about their origin and connection to the early universe.Involved junior researchers will gain expertise in a wide range of problems in cosmology and astrophysics, numerical algorithms, high performance computing, and software engineering. There will also be opportunities to tackle the challenging problem of visualizing results from large multi-dimensional computer simulations. The lead researcher will continue to integrate research activities into teaching in K-12 schools and other public venues, as well as through online learning environments.