A New Subgrid Model for AGN Feedback in Galaxy Clusters

大多数星系的中心都有超大质量黑洞。当这些黑洞吞噬气体时，它们会产生射流，射流可以在一个被称为反馈的过程中清除气体。许多星系居住在星系团中，反馈既可以影响星系的生长，也可以影响星系团的演化。这个项目将发展和完善一种方法来模拟气体吸积对反馈的影响。这种方法可以用来更好地模拟星系和星系团在宇宙时间内的成长。该项目还将开发用于课堂的基于网络的宇宙学演示。它还将支持一个面向高中女生的女生科学夏令营。该项目将完成一种用于星系团活动星系核（AGN）反馈的新型亚网格模式的开发。该模型将中心黑洞视为一个吸积粒子，并在一个已分解的控制面上使用积分计算吸积速率。然后用吸积率来确定吸积盘模型的状态，这将决定反馈的形式和效率。该模型将应用于星系团中心的三维自适应网格细化模拟，以研究两个问题：吸积盘状态转换如何与星系团核心的大规模流动相互作用；以及最亮星系团合并产生的二元性如何影响AGN反馈。现有的计算天体物理学教育网站将使用新的模拟工具进行升级，现有的外展营计划将得到改进，为额外的活动日和项目提供资源。该奖项反映了美国国家科学基金会的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

Most galaxies have supermassive black holes in their centers. As these black holes swallow gas, they produce jets that can remove gas in a process known as feedback. Many galaxies inhabit clusters of galaxies and feedback can influence both the growth of the galaxies and the evolution of galaxy clusters. This project will develop and refine a method for simulating the effect of gas accretion on feedback. This method can be used to better model the growth of galaxies and galaxy clusters over cosmic time. The project will also develop web-based demonstrations of cosmology for use in classrooms. It will also support a girls' science summer camp for high school girls.The project will complete the development of a novel sub grid mode for active galactic nucleus (AGN) feedback in clusters of galaxies. The model treats the central black hole as a sink particle and computes the accretion rate using integration over a resolved control surface. The accretion rate is then used to determine the state of an accretion disk model which will determine the form and efficiency of the feedback. The model will be applied to 3D adaptive mesh refinement simulations of the centers of clusters of galaxies to investigate two questions: how accretion disk state transitions interact with large-scale flows in cluster cores; and how binarity resulting from mergers of the brightest cluster galaxies affects AGN feedback. An existing web site for computational astrophysics education will be upgraded with new simulations tools, and an existing outreach camp program will be improved with resources for additional activity days and projects.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.