Collaborative Research: Establishing the Foundations of Black Hole Mass Measurements of AGN Across Cosmic Time

超大质量黑洞是宇宙中最大的黑洞，质量从太阳的数百万倍到数十亿倍不等。天文学的一个主要主题是了解这些黑洞是如何增长到它们的巨大质量的。该项目将通过对类星体的观测研究来研究黑洞的增长，类星体是正在快速增长的超大质量黑洞。研究人员将使用一种名为“回波映射”的方法，确定气体如何在类星体中的黑洞周围流动，并测量黑洞的质量。这项工作将使用他们团队开发的新数据分析工具和软件，使之有可能比以前的方法更准确地测量黑洞质量。他们还将分析早期观测项目的数据，以便收集大量具有准确黑洞质量测量的类星体。他们将利用这些结果来开发改进的方法来估计宇宙中最遥远的类星体中的黑洞质量。这项工作将为研究跨越宇宙历史的黑洞增长提供重要的新基础。研究人员将与天文学专业的本科生合作，专注于开展研究。他们将指导和建议考虑进入研究生院的学生，并将为“加州桥”项目的学生提供暑期研究机会。第二部分了解超大质量黑洞跨越宇宙时间的生长和演化是天文学的一个中心主题。只有当黑洞从周围吸收物质并发出类星体的明亮光芒而活跃生长时，才能识别和研究非常遥远的黑洞。测量类星体中黑洞的质量是了解黑洞如何生长并影响其环境的关键。回波映射技术是研究类星体物理性质和黑洞质量的最好工具之一。这种方法使用类星体光线随时间的变化来绘制出气体在黑洞周围的分布和运动。该项目的目标是通过结合新的观测结果和开发新的数据分析方法来推进类星体回波测绘的科学研究。研究人员将使用几个望远镜获取新的回波映射数据，并使用这些数据来绘制黑洞周围气体的分布。他们将应用我们团队开发的新数据分析方法，在物理框架内解释回波映射数据，从而能够直接确定黑洞的质量。最后，他们将对早期工作中所有可用的回波映射数据进行统一的重新分析，并使用结果来推导出对遥远类星体中黑洞质量的改进校准。这项工作将为研究整个宇宙历史上的黑洞增长提供一个严格的新基础。研究人员将与天文学专业的本科生合作，专注于开展研究。他们将指导和建议考虑进入研究生院的学生，并将为“加州桥”项目的学生提供暑期研究机会。该奖项反映了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。

Part 1Supermassive black holes are the largest black holes in the universe, ranging from millions to billions of times the mass of the Sun. A major theme in astronomy is understanding how these black holes grew to their enormous masses. This project will investigate the growth of black holes by carrying out observational studies of quasars, which are supermassive black holes that are growing rapidly. Using a method called "echo mapping", the investigators will determine how gas flows around the black holes in quasars and measure the masses of the black holes. This work will use new data analysis tools and software developed by their team that will make it possible to measure the black hole masses with higher accuracy than earlier methods. They will also analyze data from earlier observing projects in order to assemble a large collection of quasars with accurate black hole mass measurements. They will use these results to develop improved methods to estimate the masses of black holes in the most distant quasars in the universe. This work will provide an important new foundation for studies of black hole growth across the history of the cosmos. The investigators will work with undergraduate astronomy majors, focusing on conducting research. They will mentor and advise students considering going on to graduate school, and will provide summer research opportunities to students in the "Cal-Bridge" program.Part 2Understanding the growth and evolution of supermassive black holes across cosmic time is a central theme in astronomy. Very distant black holes can only be identified and studied when they are actively growing by accreting matter from their surroundings and shining brightly as quasars. Measuring the masses of the black holes in quasars is a key to understanding how black holes grow and influence their environments. The technique of "echo mapping" is one of the best tools to study the physical properties and black hole masses of quasars. This method uses the variations over time in a quasar's light to map out the distribution and motion of gas around the black hole. The goal of this project is to advance the science of quasar echo mapping through a combination of new observations and the development of new data analysis methods. The investigators will acquire new echo mapping data using several telescopes, and use the data to map the distribution of gas around the black holes. They will apply new data analysis methods developed by our team to interpret echo mapping data in a physical framework that will enable direct determination of the masses of black holes. Finally, they will carry out a uniform re-analysis of all available echo mapping data from earlier work, and use the results to derive an improved calibration of the black hole masses in distant quasars. This work will provide a rigorous new foundation for investigations of black hole growth across the history of the universe. The investigators will work with undergraduate astronomy majors, focusing on conducting research. They will mentor and advise students considering going on to graduate school, and will provide summer research opportunities to students in the "Cal-Bridge" program.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.