Collaborative Research: Constraining galaxy cluster merger dynamics with hydrodynamical simulations and novel multi-probe observations of 10 objects

星系团是解开星系形成和演化背后的奥秘的关键角色，了解这些奥秘对于揭示我们的宇宙如何演化以及了解我们自己的银河系如何开始是必要的。该项目的目标是更好地了解我们宇宙中最大束缚物体的主要生长机制：质量相似的星系团之间的重大合并。需要有深层多探测器观测数据和先进的流体动力学计算机模拟。该项目旨在通过对10个星系团的研究来显着推进我们的知识。 该项目还将通过直接培训一般和计算天体物理学的研究生和博士后研究员来加强美国的科学劳动力。项目计划还包括一个积极的教育和公共宣传方案。具体来说，调查人员将通过定期访问加布里埃利诺高中来推进发现和理解（加利福尼亚州圣加布里埃尔）;通过加州理工学院的夏季研究联系接待加布里埃利诺高中的学生，以及通过史密森学会天体物理观测站的拉丁美洲倡议计划接待马萨诸塞州东部大学的本科生，扩大代表性不足的群体的参与;并通过访问加州理工学院提供的访问加布里埃利诺高中的演示资源来加强研究和教育的基础设施。分析将侧重于10个物体，这些物体具有来自哈勃太空望远镜的引力透镜模型，以绘制天空平面（POS）投影总质量密度; X射线光谱成像，以绘制POS ICM发射率和温度;星团成员光谱学，以绘制暗物质的视线（LOS）速度;以及Sunyaev-Zel'dovich效应数据，以绘制ICM的LOS速度和投影密度。研究人员将获得关于暗物质和ICM气体的POS形态和LOS速度的完整信息。他们将与专门为这个项目制作的自定义流体动力学合并模拟的模拟观测进行比较。最终的结果将是对样本中每个星系团的合并几何形状的强大约束，这将有助于寻找新的动力学过程和评估样本的人口统计数据。该奖项反映了NSF的法定使命，并被认为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来支持。

Clusters of galaxies are key players in unraveling the mysteries behind galaxy formation and evolution, and understanding such mysteries is necessary to uncover how our Universe evolved and to learn how our own Milky Way Galaxy began. The goal of this project is to better understand the primary growth mechanism of the largest bound objects in our Universe: major mergers between galaxy clusters of similar masses. Deep, multi-probe observational data and advanced hydrodynamical computer simulations are required. This project aims to significantly advance our knowledge through the study of ten galaxy clusters. This project will also strengthen the US science workforce by directly training a graduate student and postdoctoral researcher in general and computational astrophysics. Project plans also include a vigorous education and public outreach program. Specifically, the investigators will advance discovery and understanding via regular visits to Gabrielino High School (San Gabriel, CA); broaden participation of underrepresented groups by hosting students from Gabrielino High School via the Summer Research Connection at Caltech, as well as undergraduates from colleges around Eastern Massashuetts via the Latino Initiative Program at the Smithsonian Institution Astrophysical Observatory; and enhance infrastructure for research and education by accessing the demonstration resources available from Caltech for visits to Gabrielino High School. The analysis will focus on ten objects that have gravitational lensing models from Hubble Space Telescope to map the plane-of-sky (POS) projected total mass density; X-ray spectroscopic imaging to map the POS ICM emissivity and temperature; cluster-member spectroscopy to map the line of sight (LOS) velocity of the dark matter; and Sunyaev-Zel’dovich effect data to map the LOS velocity and projected density of the ICM. The investigators will have complete information about the POS morphology and LOS velocity of both the dark matter and the ICM gas. They will compare with mock observations of custom hydrodynamical merger simulations produced specifically for this project. The end result will be a robust constraint on the merger geometry of each galaxy cluster in their sample that will enable a search for new dynamical processes and an assessment of population statistics for the sample.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.