Petascale Adaptive Mesh Simulations of Milky Way-type Galaxies and Their Environments

这个项目寻求关于星系形成和演化的几个紧迫问题的答案。它通过使用Blue Waters超级计算机来执行一套复杂的超级计算机模拟来实现这一点。研究人员将回答这样的问题：(I)银河系最早的祖先是如何形成的，今天我们在哪里可以找到他们的恒星残骸？(Ii)大质量恒星产生的电离辐射是如何逃逸出星系的，它如何影响邻近星系的性质？(Iii)对于恒星形成至关重要的气体是如何从宇宙网进入星系中心区域的，以及气体是如何返回到星际介质的？(Iv)磁场是如何在星系中播种和放大的，以及它们是如何射入(或放大)星系间介质的？该团队包括天体物理学和高性能计算方面的专家，并在使用复杂的数值工具(Enzo AMR代码)方面团结一致，该工具已经在Blue Waters上展示了其性能。该团队将与观测天文学家的合作者合作，将这些模拟应用于解释当前天文调查对本地和遥远星系的测量结果，并推动未来大型天文观测望远镜和詹姆斯·韦伯空间望远镜的观测。拟议的工作有望对正在培训的科学家产生重大影响，他们将学会在尽可能大的范围内使用尖端数值工具。该项目将让密歇根州立大学的本科生(通过密歇根州立大学S REU项目，针对女性和未被充分代表的少数民族)和博士后研究人员参与研究。该项目的科学成果将由国家超级计算应用中心的工作人员可视化，并将通过与天文馆和博物馆的预先存在的合作以及通过互联网向公众传播。此外，这些可视化将被用作该项目成员所做的外展演讲的一部分。最后，该项目产生的模拟数据将用于密歇根州立大学的计算科学课程，用于培训学生科学可视化和数据分析技术。课程材料将通过万维网向公众公布。该项目使用的具体研究方法包括创建一个广泛的模拟银河系及其环境的资料库，可用于探索各种可观察到的天体物理现象。这将是对星系形成和演化进行宇宙学模拟的第一次研究，其中包括对统计上显著数量的星系的辐射传输和/或磁流体动力学进行自洽处理，并将这些计算应用于解释最近与星系间和银河系周围介质、星系和河外磁场以及高红移星系形成有关的观测结果。此外，在该项目过程中产生的模拟数据以及各种数据产品将通过新成立的国家数据服务处向公众提供。这些数据将被天体物理研究界使用，并将使研究人员能够解决与星系形成和演化有关的更广泛的问题，而不是仅作为该项目的一部分，从而利用Blue Waters上可用的计算资源。

This project seeks answers to several pressing questions about the formation and evolution of galaxies. It does so by using the Blue Waters supercomputer to perform a suite of sophisticated supercomputer simulations. The investigators will address such questions as: (i) How did the earliest progenitors of the Milky Way galaxy form, and where can we find their stellar remnants today? (ii) How does the ionizing radiation produced by massive stars escape from galaxies, and how does it affect the properties of neighboring galaxies? (iii) How does the gas that is critical for star formation get from the cosmic web into the central regions of galaxies, and how is gas returned to the intergalactic medium? (iv) How are magnetic fields seeded and amplified in galaxies, and how are they ejected into (or amplified in) the intergalactic medium?The team includes experts in astrophysics as well as in high performance computing, and is united in the use of a sophisticated numerical tool (the Enzo AMR code) that has already demonstrated its performance on Blue Waters. The team will work with observational astronomer collaborators to apply these simulations to the interpretation of measurements of both local and distant galaxies from current astronomical surveys, and to motivate future observations by the Large Synoptic Survey Telescope and the James Webb Space Telescope.The proposed work promises to have significant impact on scientists in training, who will learn to use cutting-edge numerical tools at the largest possible scale. The project will involve undergraduate students at Michigan State University (through MSU?s REU program, which targets women and under-represented minorities) and postdoctoral researchers in the research efforts. Scientific results from this program will be visualized by staff at the National Center for Supercomputing Applications, and will be disseminated to the public via pre-existing collaborations with planetaria and museums, and via the Internet. In addition, these visualizations will be used as part of outreach talks given by members of this project. Finally, the simulation data produced as a result of this project will be used in computational science courses at Michigan State University, where it will be used to train students in scientific visualization and data analysis techniques. The resulting curricular materials will be made available to the public via the World Wide Web.The specific research methods used in this project include the creation of an extensive library of simulated Milky Way-like galaxies and their environments that can be used to explore a wide range of observable astrophysical phenomena. This will be the first study to perform cosmological simulations of galaxy formation and evolution that include self-consistent treatments of radiation transport and/or magnetohydrodynamics for a statistically significant number of galaxies, and to apply these calculations to the interpretation of recent observations relating to the intergalactic and circumgalactic medium, galactic and extragalactic magnetic fields, and high redshift galaxy formation. Furthermore, the simulation data produced during the course of this project, as well as a wide range of data products, will be made publicly available via the nascent National Data Service. This data will be usable by the astrophysical research community, and will enable researchers to address a much broader range of questions regarding galaxy formation and evolution than can be done as a part of this project alone, thus leveraging the computational resources available on Blue Waters.