Binary Black Holes at the Extremes in the Era of Gravitational Wave Astronomy

该奖项支持引力波探测器数据分析的研究，并解决了NSF“宇宙之窗”大构想的优先领域。这个研究项目致力于引力波的分析和建模。当宇宙中密度最大的物体（如黑洞和中子星）绕轨道运行并发生碰撞时，就会在空间和时间的结构中产生这些涟漪。由美国国家科学基金会资助的LIGO和欧洲处女座合作项目对引力波的探测，为研究宇宙打开了一扇新的窗口，揭示了以前看不见的事件，比如黑洞成对合并。奥斯汀相对论小组的成员将作为LIGO合作项目的成员参与对引力波的分析，帮助推断这些涟漪来源的性质。为了确保从引力波探测中获得最大的科学效益，引力波产生的模型需要不断改进。研究小组成员将在超级计算机上进行数值模拟，以探索黑洞对的轨道和碰撞。重点将放在极端的配置上——比如质量非常不均匀和轨道复杂的系统——目标是在这些情况下，为引力波是如何产生的笔和纸近似建立新的联系。这些研究活动将为研究生提供高性能计算和数据分析方面的培训，这些技能对社会有很大的需求，对社会有很大的好处。此外，该小组的成员将参与外展活动，以教育和激励公众了解这一新的物理和天文学领域。最后，该小组的成员将参与向高中女性的推广活动，以促进STEM领域的多样性。本项目主要研究质量差异较大的双黑洞，其引力波的建模具有一定的挑战性。这个项目将把这些双星的数值模拟与解析近似联系起来，解析近似能够模拟质量非常不等的双星，特别是自力近似。有针对性的模拟将测试自作用力和其他近似值，为其预测提供独立验证，揭示其局限性，并指出用于GW科学的改进方法。进行比较的关键工具将是不变的量，如黑洞的红移因子和轨道频移。这些双星模型的进展将对当前的GW探测器时代产生直接的好处，并将对未来太空任务的成功至关重要。此外，PI和研究小组的其他成员将直接参与对引力波的分析。该小组的成员使用贝叶斯参数估计测量产生这些波的二进制的特性。这些推论是利用引力波探测来理解双黑洞的数量、从对双中子星的观测推断核状态方程、检验相对论以及利用引力波测量宇宙膨胀的关键的第一步。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。

This award supports research in gravitational wave detector data analysis and it addresses the priority areas of NSF's "Windows on the Universe" Big Idea. This research project is devoted to the analysis and modeling of gravitational waves. These ripples in the very fabric of space and time are produced when the densest objects in the Universe -- such as black holes and neutron stars -- orbit and collide. The detection of gravitational waves by the NSF-funded LIGO and European Virgo collaborations has opened up a new window on the Universe, revealing previously invisible events like pairs of black holes merging. Members of the Austin Relativity group will participate in the analysis of gravitational waves as members of the LIGO collaboration, helping to infer the properties of the sources of these ripples. To ensure the maximum scientific benefit from the detection of gravitational waves, models for how these waves are produced require continuing refinement. Members of the research group will perform numerical simulations on supercomputers in order to explore the orbit and collision of pairs of black holes. The focus will be on extreme configurations -- such as systems with very unequal masses and complicated orbits -- with the goal of making new connections to pen and paper approximations for how gravitational waves are produced in these cases. These research activities will provide training for graduate students in high-performance computing and data analysis, skillsets which are in great demand and of great benefit to society. In addition, members of the group will engage in outreach activities in order to educate and inspire the public about this new field of physics and astronomy. Finally, members of the group will participate in outreach to high school women, in order to promote diversity within STEM fields.This project focuses on the study of binary black holes with significantly different masses, whose gravitational waves are challenging to model. This project will connect numerical simulations of these binaries with analytical approximations which are capable of modeling binaries with very unequal masses, in particular the self-force approximation. Targeted simulations will test the self-force and other approximations, provide independent verification of their predictions, reveal their limitations, and point to refined approaches for use in GW science. The key tool for making comparisons will be invariant quantities, such as the redshift factor and orbital frequency shifts of the black holes. Advances in modeling these binaries will have immediate benefits for the current era of GW detectors, and will be crucial for the success of future, space-based missions. In addition, the PI and other members of the research group will directly participate in the analysis of gravitational waves. Members of the group measure the properties of these binaries which produce these waves using Bayesian parameter estimation. These inferences are a crucial first step in the use of gravitational wave detections for understanding the population of binary black holes, inferring the nuclear equation of state from observations of binary neutron stars, testing the theory of relativity, and using gravitational waves to measure cosmic expansion.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.