Towards a Predictive Theory of Galaxy Formation: Cosmological Gas Accretion and Galactic Outflows

走向星系形成的预测理论：宇宙学气体吸积和星系流出

• 批准号: 1312095
• 负责人: Lars Hernquist
• 金额: $ 74.62万
• 依托单位: Harvard University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2013
• 资助国家: 美国
• 起止时间: 2013-09-01 至 2017-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1312095&HistoricalAwards=false
• 关键词: Towards; Predictive; Theory; Galaxy; Formation

Cosmological simulations of galaxy formation provide the most complete approach for understanding the evolution of structure in the universe. The ultimate goal of such simulations is to trace the formation of galaxies from first principles; but the enormous dynamic range, and the many poorly understood physical effects involving baryonic matter in galaxies, make this an extremely difficult computational challenge. In this project, a model for the visible universe will be constructed using state-of-the-art cosmological simulations. The simulations will include both dark matter and baryons, and will employ a novel moving mesh technique implemented in the new code AREPO. Using convergence tests, it will be possible to determine which results are robust to variations in the treatment of star formation, black hole growth, and feedback, which will be handled in ways that are more physically motivated than in earlier studies. The scientific effort will focus on understanding: 1) the formation of galactic disks in a cosmological context and the impact of feedback on galaxy morphology and kinematics; 2) the nature of gas inflows into galaxy halos and the accretion of gas by disks; 3) the interaction between accreted gas and galactic outflows of chemically enriched material and consequences for the circumgalactic medium; and 4) the co-evolution of galaxies and their central supermassive black holes. The simulation results, including snapshots of the full simulations, galaxy catalogs, images, and videos, will be made available to the research community through a web-based interface. The project will support the work of a postdoctoral scholar and a graduate student; in addition, a series of lectures will be developed to be given to high school students in Cambridge, MA on topics covering the evolution of the Universe and its constituents.

星系形成的宇宙学模拟为理解宇宙结构的演化提供了最完整的方法。这种模拟的最终目标是从第一原理追踪星系的形成;但是巨大的动态范围，以及许多对星系中重子物质的物理效应知之甚少，使得这是一个极其困难的计算挑战。在这个项目中，将使用最先进的宇宙学模拟来构建可见宇宙的模型。模拟将包括暗物质和重子，并将采用新代码AREPO中实现的新移动网格技术。使用收敛检验，将有可能确定哪些结果对处理星星形成、黑洞生长和反馈的变化是鲁棒的，这些结果将以比早期研究更物理动机的方式处理。科学工作的重点是了解：⑴宇宙学背景下星系盘的形成以及反馈对星系形态和运动学的影响; ⑵流入星系晕的气体的性质以及星系盘吸积气体的性质; ⑶吸积气体与化学富集物质流出星系之间的相互作用以及对环星系介质的影响; 4）星系与中心超大质量黑洞的共同演化。模拟结果，包括完整模拟的快照，星系目录，图像和视频，将通过基于网络的界面提供给研究界。该项目将支持一名博士后学者和一名研究生的工作;此外，还将为马萨诸塞州剑桥的高中生举办一系列讲座，主题涉及宇宙及其组成部分的演变。