Collaborative Research: Understanding Compact Binary Formation With Gravitational Wave Observations

美国的激光干涉仪引力波天文台（LIGO）和欧洲的处女座探测器开启了宇宙探索的新时代。这些观测解决了物理学和天文学中的老难题，并揭示了一群新的天体。LIGO和Virgo拥有升级的灵敏度和新的探测器，将很快观测到更大的源目录。这个研究项目有两个目标。第一种方法是使用即将进行的观测运行中的事件目录，以便更好地理解紧凑二进制是如何形成和合并的。二是研究如何利用引力波来研究早期宇宙，测量其膨胀速率，并推断暗物质粒子的性质。该项目的调查人员将通过在学校、夏令营和实习的讲座和示范来教育宾夕法尼亚州中央县和巴尔的摩地区的学生。他们将继续举办成功的“极限物理学和天体物理学”（PAX）系列研讨会。此外，他们还将发起一系列新的研讨会，讨论LIGO、Virgo和KAGRA发现的致密天体的数量：“引力波数量：下一步是什么？”(或“POPX”)。自从LIGO和处女座发现紧凑的双星合并以来，天体物理学家已经探索了几种不同的形成场景。精确测量质量、自旋和红移的合并事件目录对于推断致密双星合并的频率、它们是如何形成的以及它们的红移演化至关重要。此外，紧凑的双星源可以提供精确的距离测量。再加上电磁观测到的红移，这是推断宇宙膨胀率的新工具。在过去的二十年里，这个团队的成员开创了解决这些问题的方法，并开发了公开的工具。该项目将利用LIGO （Virgo）和KAGRA （KAGRA）接下来两次观测的更大引力波目录来解决天体物理学和宇宙学中尚未解决的问题。研究人员将在场双星的种群合成中实现天体物理自旋模型。他们将开发快速、一致的动态地层通道模型，比较人口推断工具，并研究波形系统学如何影响引力波天文学。本文还将研究紧致双星系统的随机前景及其对模型推理的影响。它将利用引力波观测来解决哈勃望远镜的张力，并探索暗物质和原始黑洞的特性。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。

The Laser Interferometer Gravitational-Wave Observatory (LIGO) in the US and the Virgo detector in Europe have ushered in a new era in the exploration of the Universe. These observations have resolved old puzzles in physics and astronomy, and they have revealed a new population of astronomical objects. LIGO and Virgo with upgraded sensitivities and new detectors will soon observe a much larger catalog of sources. This research program has two goals. The first is to use the catalog of events from the upcoming observing runs to better understand how compact binaries form and merge. The second is to study how gravitational waves can be used to study the early Universe, measure its expansion rate, and infer the properties of dark matter particles. The program’s investigators will educate students in Centre County, PA and in the Baltimore area through lectures and demonstrations at schools, summer camps, and internships. They will continue to organize the successful "Physics and Astrophysics at the Extreme" (PAX) series of workshops. In addition, they will initiate a new series of workshops on the populations of compact objects discovered by LIGO, Virgo and KAGRA: "Gravitational wave populations: what's next?" (or "POPX").Since the discovery of compact binary mergers by LIGO and Virgo, astrophysicists have explored several different formation scenarios. A catalog of merger events with precisely measured masses, spins and redshifts is critical to infer how often compact binaries merge, how they form, and their redshift evolution. Moreover, compact binary sources can provide accurate distance measurements. Together with the redshift from electromagnetic observation of their hosts, this is a new tool for deducing the expansion rate of the Universe. Over the past two decades, the members of this team have pioneered methods to address these problems and have developed tools that have been made public. This program will use the larger gravitational-wave catalogs from the next two observing runs of LIGO, Virgo and KAGRA to address unsolved problems in astrophysics and cosmology. The investigators will implement astrophysical spin models in population synthesis for field binaries. They will develop rapid, consistent models of dynamical formation channels, compare tools for population inference, and study how waveform systematics affect gravitational-wave astronomy. The proposal will also study stochastic foregrounds of compact binary systems and their effect on model inference. It will harness gravitational-wave observations to resolve the Hubble tension, and explore the properties of dark matter and primordial black holes.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.