CAREER: Modeling the Evolution of Massive Galaxies with Enzo-E

在过去的几十年里，我们通过观测和详细的计算机模拟，在理解星系的形成和演化方面取得了巨大的进步。然而，许多关键问题仍然没有得到充分的理解。例如，大多数大质量椭圆星系，宇宙中最古老和最大质量的结构之一，以及超大质量黑洞(SMBH)的宿主，停止形成恒星，过渡到被动演化的系统。虽然这种“猝灭”的确切机制尚不清楚，但SMBH似乎通过抑制来自环星系介质(CGM)的新鲜气体的流入发挥了关键作用。新鲜气体是恒星形成的原材料。PI将以足够的空间分辨率对一个大质量星系的形成和演化进行计算机模拟，以解决CGM的复杂结构和在那里发生的小尺度物理过程。这项工作将为大规模宇宙学模拟提供信息和补充，并将为三名研究生提供尖端星系模拟方面的指导和培训。本科生也将参与其中，调查人员将参与到当地高中和公共天文馆表演中。为了更好地了解大质量星系的演化，研究人员和她的团队将进行一项非常高分辨率的数值研究，使用宇宙学变焦模拟，重点关注单个大质量星系的形成，同时一直跟踪它的演化到当前纪元(z=0)。这项工作的主要目标是了解(1)SMBH是如何在大质量星系中形成和生长的，(2)SMBH“反馈”如何导致恒星形成猝灭，(3)CGM的结构和演化，以及(4)卫星星系的演化是如何受到影响的。该团队将使用新开发的Enzo-E，这是针对艾级时代的原始Enzo代码的高度可伸缩的重新设计。他们将开发一种新的最先进的SMBH形成/反馈模型，该模型将被添加到公开可用的代码中并与社区共享。拟议中的模拟将强制对星系的CGM进行改进，提供围绕大质量星系的这个主要气藏的前所未有的细节，这可能在调节SMBH和恒星形成的燃料方面发挥关键作用。这项研究将深入了解SMBH、CGM和大质量星系中恒星形成之间的复杂相互作用，并将提供一个框架来模拟(例如)宇宙射线、尘埃和辐射转移。这一奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

The past few decades have seen tremendous advances in our understanding of galaxy formation and evolution using both observations and detailed computer simulations. However, many key questions are still not fully understood. For example, most massive elliptical galaxies, among the oldest and most massive structures in the universe and hosts of supermassive black holes (SMBH), cease forming stars and transition into passively evolving systems. While the precise mechanisms underpinning such "quenching" are unclear, SMBHs appear to play a key role by suppressing the infall of fresh gas - the raw material of star formation - from the circumgalactic medium (CGM). The PI will conduct a computer simulation of a massive galaxy's formation and evolution with spatial resolution sufficient to resolve the CGM's complex structure and the small-scale physical processes occurring there. This work will inform and complement large-scale cosmological simulations and will provide mentoring and training for three graduate students in cutting edge galaxy simulations. Undergraduate students will also be involved, and the investigator will engage in outreach to local high schools and public planetarium shows. To better understand the evolution of massive galaxies, the investigator and her group will conduct a very high- resolution numerical study using a cosmological-zoom simulation focusing on the formation of a single massive galaxy while following its evolution all the way down to the current epoch (z = 0). The major objectives of this work are to understand (1) how SMBHs form and grow in massive galaxies, (2) precisely how SMBH "feedback" leads to star formation quenching, (3) the structure and evolution the CGM, and (4) how the evolution of satellite galaxies is affected. The team will use the newly developed Enzo-E, which is a highly scalable redesign of the original Enzo code for the exascale era. They will develop a new state-of-the-art SMBH formation/feedback model, which will be added to the publicly available code and shared with the community. The proposed simulations will force enhanced refinement in the galaxy's CGM, providing unprecedented details of this major gas reservoir around massive galaxies, which likely plays a key role in regulating the fueling of both SMBHs and star formation. This research will provide insight into the complex interplay between SMBHs, the CGM, and star formation in a massive galaxy, and it will provide a framework for simulating the effects of (e.g.) cosmic rays, dust, and radiative transfer.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.