Searching for the Stochastic Gravitational Wave Background with Advanced Gravitational Wave Detectors

用先进的引力波探测器寻找随机引力波背景

• 批准号: 2110238
• 负责人: Vuk Mandic
• 金额: $ 44.2万
• 依托单位: University of Minnesota-Twin Cities
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2021
• 资助国家: 美国
• 起止时间: 2021-08-15 至 2024-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2110238&HistoricalAwards=false
• 关键词: Searching; Stochastic; Gravitational; Wave; Background

This award supports research in gravitational waves data analysis and it addresses the priority areas of NSF's "Windows on the Universe" Big Idea. Stochastic gravitational-wave background arises as an incoherent superposition of many gravitational wave signals generated by uncorrelated astrophysical and cosmological sources throughout the universe. Measuring the astrophysical component of this background, for example due to mergers of black holes and/or neutron stars, would provide information about how the structure in the universe formed. Similarly, measuring the cosmological component of this background would provide unique information about the universe when it was a fraction of a second old, and about the physical laws that apply to very high energy scales that are not reproducible in laboratories. This project aims to search and detect the stochastic gravitational wave background using the upcoming Advanced LIGO, Virgo, and Kagra data, as well as to characterize its composition and study implications for different astrophysical and cosmological models. The project will enable involvement of undergraduate and graduate students in frontier research, and it will promote gravitational-wave science to the general public.Stochastic gravitational-wave background (SGWB) arises as an incoherent superposition of many gravitational wave signals generated by uncorrelated astrophysical or cosmological sources throughout the universe. This project aims to search for (and detect) the SGWB using the upcoming aLIGO, aVirgo, and KAGRA data from the fourth observing run (O4) in 2022/23, leveraging the improved detector sensitivities expected for O4 and deploying two search techniques. The traditional cross-correlation based search is expected to be 10 times more sensitive than the most recent results based on the first three observation runs, with another factor of 4 improvement expected with the A+ detector sensitivities in 2024 and beyond. For the specific case of the SGWB due to binary black hole mergers, the full Bayesian Search will be developed with the potential to improve the sensitivity by ~1000 times relative to the cross-correlation search. These searches will probe the high-redshift distribution of the compact binary systems and provide information about their formation and evolution. They will also constrain cosmological SGWB models, such as inflationary, phase transitions, and cosmic (super)string models, and therefore probe the physics of fundamental interactions at very high energies, unachievable in laboratories. Both the cross-correlation and the Bayesian SGWB searches will estimate the directional content of the SGWB, enabling future studies correlating the SGWB with electromagnetic tracers of matter structure in the universe, such as galaxy counts or gravitational lensing. In addition to involving graduate and undergraduate students in frontier research, this project includes a series of activities designed to bring the excitement of the gravitational-wave science to broad communities in the Twin Cities and Minnesota, including physics demonstrations and presentations in K-12 schools and data analysis projects for implementation in K-12 classrooms.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.

该奖项支持引力波数据分析研究，并解决美国国家科学基金会“宇宙之窗”大构想的优先领域。随机引力波背景是由整个宇宙中不相关的天体物理和宇宙学源产生的许多引力波信号的不相干叠加而产生的。测量这种背景的天体物理成分，例如由于黑洞和/或中子星的合并，将提供有关宇宙结构如何形成的信息。同样，测量这种背景的宇宙学成分将提供有关宇宙在几分之一秒的年龄时的独特信息，以及适用于实验室无法重现的极高能量尺度的物理定律的信息。该项目旨在利用即将推出的 Advanced LIGO、Virgo 和 Kagra 数据来搜索和探测随机引力波背景，并表征其组成并研究对不同天体物理和宇宙学模型的影响。该项目将使本科生和研究生能够参与前沿研究，并将向公众推广引力波科学。随机引力波背景（SGWB）是由不相关的天体物理或引力波信号产生的许多引力波信号的不相干叠加而产生的。整个宇宙的宇宙源。该项目旨在利用 2022/23 年第四次观测运行 (O4) 即将推出的 aLIGO、aVirgo 和 KAGRA 数据来搜索（和探测）SGWB，利用 O4 预期改进的探测器灵敏度并部署两种搜索技术。传统的基于互相关的搜索预计比基于前三次观测运行的最新结果的灵敏度高 10 倍，预计 2024 年及以后 A+ 探测器的灵敏度将再提高 4 倍。对于由于二元黑洞合并而导致的 SGWB 的具体情况，将开发完整的贝叶斯搜索，相对于互相关搜索，有可能将灵敏度提高约 1000 倍。这些搜索将探测致密双星系统的高红移分布，并提供有关其形成和演化的信息。他们还将约束宇宙学 SGWB 模型，例如暴涨模型、相变模型和宇宙（超）弦模型，从而探索实验室无法实现的极高能量下基本相互作用的物理现象。互相关和贝叶斯 SGWB 搜索都将估计 SGWB 的方向内容，从而使未来的研究能够将 SGWB 与宇宙中物质结构的电磁示踪物（例如星系计数或引力透镜）相关联。 除了让研究生和本科生参与前沿研究外，该项目还包括一系列旨在将引力波科学的乐趣带给双子城和明尼苏达州广大社区的活动，包括在 K-12 学校进行物理演示和演讲该奖项反映了 NSF 的法定使命，并通过使用基金会的智力价值和更广泛的影响审查标准进行评估，被认为值得支持。