Collaborative Research: Modeling the Reionization of the Intergalactic Medium

合作研究：模拟星际介质的再电离

• 批准号: 1312724
• 负责人: Scott Anderson
• 金额: $ 37.41万
• 依托单位: University of Washington
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2013
• 资助国家: 美国
• 起止时间: 2013-09-01 至 2016-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1312724&HistoricalAwards=false
• 关键词: Collaborative; Research; Modeling; Reionization; Intergalactic

Reionization is the epoch during which intergalactic hydrogen was ionized, the period when the first galaxies formed and when the intergalactic gas was significantly heated, to tens of thousands of degrees Kelvin, but despite its importance, little is known definitively about this phase transition. This project aims to resolve the impact of self-shielding systems, perhaps the largest still unquantified uncertainty in current models of reionization, through a rigorous program of numerical simulations. Prior radiative transfer simulations did not have the resolution to capture self-shielding systems, and thus misestimated the total number of recombinations, biasing their predictions for the duration of reionization.Starting with a physically motivated model that includes self-shielding regions and explores parameter space with relatively inexpensive simulations, the work will use those results to carry out the first simulations with sufficient resolution to resolve self-shielding systems. Those simulations will verify the results from the initial work, and will be a resource for statistical studies on the structure of reionization. This study will understand how the violent relaxation of gas from photoheating during reionization influences dense gas and, hence, self-shielding systems, and will generally aid the interpretation of all observations of the reionization era.The data set of state-of-the-art reionization simulations will be made public and can be analyzed by the scientific community. Past work by this team has been used in many unaffiliated studies and the new results should also be of great utility. Similarly, the publicly available archive of visualizations will both educate the public and help to develop scientists? intuition. Supported undergraduate researchers will be drawn preferentially from under-represented groups, and the researchers intend public lectures at schools and other venues.

再电离是星系间氢被电离的时期，也就是第一批星系形成和星系间气体显著加热到数万开尔文的时期，但尽管它很重要，人们对这一相变却知之甚少。这个项目旨在通过一个严格的数值模拟程序来解决自屏蔽系统的影响，这可能是当前再电离模型中最大的仍未量化的不确定性。以前的辐射传输模拟不具有捕获自屏蔽系统的分辨率，因此错误地估计了重组的总数，从而偏向了他们对电离持续时间的预测。从包括自屏蔽区的物理激励模型开始，并用相对廉价的模拟来探索参数空间，该工作将使用这些结果来进行具有足够分辨率的第一次模拟来解析自屏蔽系统。这些模拟将验证最初工作的结果，并将成为再电离结构统计研究的资源。这项研究将了解在再电离过程中光热产生的气体的剧烈松弛如何影响致密气体，从而影响自屏蔽系统，并通常将有助于解释所有对再电离时代的观测。最先进的再电离模拟的数据集将被公布，并可被科学界分析。这个团队过去的工作已经被用于许多独立的研究，新的结果也应该是非常有用的。同样，可公开获得的可视化档案将既教育公众，又有助于培养科学家？直觉。受支持的本科生研究人员将优先从代表性不足的群体中挑选出来，研究人员打算在学校和其他场所进行公开演讲。