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。当这些黑洞吞下气体时，它们会产生射流，可以在一个被称为反馈的过程中移除气体。许多星系居住在星系团中，反馈可以影响星系的生长和星系团的演化。该项目将开发和完善一种模拟气体积聚对反馈影响的方法。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生长。该项目还将开发基于网络的宇宙学演示，供课堂使用。该项目还将支持为高中女生举办的女生科学夏令营，并将完成星系团活动星系核反馈的新型次网格模式的开发。该模型将中心黑洞视为一个下沉粒子，并在一个解析控制面上积分计算吸积率。吸积率，然后用来确定状态的吸积盘模型，这将决定的形式和效率的反馈。该模型将被应用到3D自适应网格细化模拟的星系团的中心，调查两个问题：吸积盘状态转换如何与大规模的流量在集群核心的相互作用;以及如何二进制合并产生的最明亮的星系团星系影响AGN反馈。现有的计算天体物理学教育网站将升级新的模拟工具，现有的外展营计划将得到改善，增加活动日和项目的资源。该奖项反映了NSF的法定使命，并已被认为是值得通过使用基金会的智力价值和更广泛的影响审查标准进行评估的支持。

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.