Collaborative Research: Modelling the Turbulent Galaxy Formation

合作研究：模拟湍流星系的形成

• 批准号: 1412271
• 负责人: Alexei Kritsuk
• 金额: $ 38.8万
• 依托单位: University of California-San Diego
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2014
• 资助国家: 美国
• 起止时间: 2014-08-15 至 2018-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1412271&HistoricalAwards=false
• 关键词: Collaborative; Research; Modelling; Turbulent; Galaxy; Collaborative; Research; Modelling; Turbulent; Galaxy

Anywhere that there is a fluid in motion, whether liquid or gas, there will be turbulence. These disturbances to the flow can be very significant, but their possibly profound effect on the formation of galaxies out of the cosmic gas remains an area of mystery in our fundamental understanding of how the Universe evolves. This work seeks to correct this lack, using high powered computers to carry out novel numerical simulations with very high resolution. For the first time, pretty well all of the physics involved in forming stars within galaxies will be included. The calculations will be intimately connected with telescope data, both checking the computer results and helping to understand the observations. The new ideas will also be useful for other studies of turbulent fluids.Cosmic gas flows have high velocities, span enormous scales, and are highly turbulent, but the possibly profound effects of turbulence on galaxy formation are largely unexplored. This project is a systematic exploration of turbulence and its effects on accretion flows, star formation, and the structure of galaxies, in self-consistent cosmological simulations using adaptive mesh refinement (AMR). Part of the work will implement and test a novel model for sub-grid scale turbulence and use it to estimate local turbulent stresses. This model will be used to add new physically-motivated prescriptions for star formation into the galaxy formation simulations, incorporating a rich set of physical processes thought to be critical for comparison with observations, including modeling of molecular hydrogen, chemical enrichment and evolution, dust formation and destruction, radiative transfer of ionizing and far-ultraviolet radiation, star formation, and stellar feedback with radiation pressure and cosmic rays. Observational comparisons will test and inform the theoretical models, while the simulation results will help to understand the data. Scientific results will include quantifying the effects of turbulence on the cold accretion gas flows onto galaxies, assessing the relative contribution of dynamical drivers of turbulence, and quantifying the effects of turbulence on the density structure of the gas. The emphasis on observational comparisons will make this study particularly valuable for interpreting the results from current and future facilities. Both the methods and the results will be of value for other simulations and for semi-analytic models. The simulations also lend themselves well to high-fidelity, scientifically-accurate visualizations well suited to the high resolution environment of full-dome planetarium projectors, but of value to all planetaria.

无论是液体还是气体，都会有湍流。 这些对流动的干扰可能非常重要，但是它们可能对宇宙气体形成星系的形成产生深远的影响，在我们对宇宙如何发展的基本理解中仍然是一个神秘的领域。 这项工作旨在纠正这种缺乏，使用高功率计算机来进行非常高分辨率的新型数值模拟。 首次将包括所有参与星系中恒星的物理学。 计算将与望远镜数据密切相关，既检查计算机结果又有助于理解观察结果。 新想法也将用于其他湍流研究。COSMIC气流具有较高的速度，巨大的尺度和湍流，但是湍流对银河系形成的深远影响很大程度上是没有探索的。 该项目是对湍流的系统探索及其对使用自适应网格改进（AMR）的自洽宇宙学模拟中的湍流，恒星形成和星系结构的影响。 一部分工作将实施和测试一个新型模型，以用于亚电网尺度湍流，并使用它来估计局部湍流应力。 This model will be used to add new physically-motivated prescriptions for star formation into the galaxy formation simulations, incorporating a rich set of physical processes thought to be critical for comparison with observations, including modeling of molecular hydrogen, chemical enrichment and evolution, dust formation and destruction, radiative transfer of ionizing and far-ultraviolet radiation, star formation, and stellar feedback with radiation pressure and cosmic rays. 观察比较将测试并告知理论模型，而模拟结果将有助于理解数据。 科学的结果将包括量化湍流对星系中冷积聚气流的影响，评估湍流动力学驱动因素的相对贡献，并量化湍流对气体密度结构的影响。 对观察比较的重视将使这项研究对于解释当前和未来设施的结果特别有价值。 方法和结果对于其他模拟和半分析模型都具有价值。 这些模拟还非常适合高保真性，科学准确的可视化效果，非常适合全盘人天文馆投影仪的高分辨率环境，但对所有行星都具有价值。