From Single to Statistical:The Dawn of Gravitational-Wave Astrophysics and Cosmology

该奖项支持相对论和相对论天体物理学的研究，并阐述了美国国家科学基金会“宇宙之窗”宏伟构想的优先领域。2015年9月14日，在不到一秒钟的时间里，LIGO仪器探测到两个相撞超过10亿光年的黑洞，引力波天体物理学领域应运而生。不到两年后，2017年8月17日，在12个小时的时间里，引力波多信使天文学领域诞生了，探测到了两颗中子星碰撞产生的引力波和光。在接下来的几年里，将探测到更多的碰撞，这个项目将探索这些来源将教会我们关于物理学、天体物理学和宇宙学的什么。该项目的重点是了解被探测系统的质量分布如何帮助我们了解宇宙是如何产生黑洞和中子星的。这与宇宙如何产生恒星有关，而恒星又与宇宙如何产生对生命至关重要的元素有关。除了探索这些引人入胜的问题并发布结果以帮助推动该领域的发展外，该小组还将开展与引力波和黑洞有关的广泛教育和推广活动。该项目将分析来源目录并确定潜在的人口分布。PI将检查检测到的双星中的组件紧凑物体的质量分布。特别是，PI将探索假定的较低质量间隙(最大质量的中子星和最小质量的黑洞之间)以及较高质量间隙(缺少质量为50个太阳质量的黑洞)。类似地，PI将探索布居的自旋和质量比分布，以及所有这些分布的红移演化。描述这些分布及其演化，将使我们了解黑洞和中子星的形成和演化，以及包含它们的双星。随着我们对分布的理解的提高，从这些基本分布中刻画异常值的能力也在提高。PI将进一步研究这一过程，既强调离群值的性质，又发展基于总体的参数估计。此外，PI将基于这些分布研究相关的天体物理约束，包括使用种群合成对这些探测进行正向建模，以及中子星状态方程的机器学习方法。这一奖项反映了NSF的法定任务，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。

This award supports research in relativity and relativistic astrophysics and it addresses the priority areas of NSF's "Windows on the Universe" Big Idea. In a fraction of a second on September 14, 2015, the field of gravitational-wave astrophysics was born with the detection by the LIGO instruments of two black holes colliding over a billion lightyears away. Less than two years later, over the span of 12 hours on August 17, 2017, the field of gravitational- wave multi-messenger astronomy was born with the detection of both gravitational-waves and light from the collision of two neutron stars. Over the next years many additional collisions will be detected, and this project will explore what these sources will teach us about physics, astrophysics, and cosmology. The project focuses on learning about how the distribution of the masses of the detected systems help us understand how the Universe makes black holes and neutron stars. This relates to how the Universe makes stars, which in turn relates to how the universe makes the elements which are crucial to life. In addition to exploring these fascinating questions and publishing results to help move the field forward, the group will also perform extensive education and outreach activities related to gravitational-waves and black holes.The project will analyze the source catalogs and determine underlying population distributions. The PI will examine the mass distribution of the component compact objects in the detected binaries. In particular, the PI will explore both the putative lower mass gap (between the most massive neutron star and the least massive black hole), as well as the upper mass gap (a dearth of black holes of mass 50 solar masses ). Similarly, the PI will explore the spin and mass ratio distributions of the population, as well as the redshift evolution of all of these distributions. Characterizing these distributions, and their evolution, will teach us about the formation and evolution of black holes and neutron stars, as well as binaries that contain them. As our understanding of the distributions improves, the ability to characterize outliers from these underlying distributions also improves. The PI will further study this process, both highlighting the nature of outliers, as well as developing population-based parameter estimation. Furthermore, the PI will study associated astrophysical constraints based on these distributions, including forward modeling of these detections using population synthesis, and machine learning approaches to the equation of state of neutron stars.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.