Collaborative Research: Modeling the Reionization of the Intergalactic Medium

再电离是星系间氢被电离的时期，这是第一个星系形成的时期，星系间气体被显著加热到数万开尔文。尽管它很重要，但对这一相变的确切了解却很少。该项目旨在通过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尚未量化的不确定性。先前的辐射传输模拟没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，使再电离持续时间的预测有偏差。从包括自屏蔽区域的物理驱动模型开始，并通过相对廉价的模拟探索参数空间，该工作将利用这些结果进行具有足够分辨率的第一次模拟，以解决自屏蔽系统。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料。这项研究将理解再电离期间光加热产生的气体的剧烈弛豫如何影响致密气体，从而影响自屏蔽系统，并将总体上有助于解释所有再电离时代的观测结果。最先进的再电离模拟数据集将被公开，并可供科学界分析。该团队过去的工作已用于许多非附属研究，新的结果也应该具有很大的实用性。同样，公开的可视化档案既可以教育公众，也可以帮助培养科学家。的直觉。受资助的本科生研究人员将优先从代表性不足的群体中挑选，研究人员打算在学校和其他场所进行公开讲座。

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.