Searches for Gravitational Wave Transients: Data Analysis for Advanced LIGO and A+ LIGO

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。由阿尔伯特·爱因斯坦的广义相对论预言的引力波是由相对论天体物理系统在时空结构中产生的涟漪。引力波一百年来一直没有被探测到，直到2015年，Advanced LIGO从两个相撞的黑洞观测到了GW，开启了多信使天文学领域的一场革命。这一发现证实了广义相对论的一个重大预测，并打开了一扇前所未有的了解宇宙的新窗口。引力波提供了对复杂天体物理系统的直接探测。自2015年以来，LIGO及其欧洲合作伙伴仪器处女座报告了50多起GW事件，目前正在积极调查中。已向天文学社区发送了许多公共警报，从而能够对这些事件进行多信使观测。在接下来的几年里，随着先进的LIGO达到其设计灵敏度，以及其他仪器加入全球GW探测器网络，预计将探测到数百个信号源。当LIGO完全升级到A+配置时，预计会有更高的检测率。GW观测将解决关键的研究问题，包括黑洞和中子星的形成和演化，致密天体在高能辐射发射中的作用，核物质的性质，伽马射线爆发的性质，并探索宇宙的结构和演化，并可能发现超越广义相对论的物理学。这些研究项目将研究一些最极端的天体物理事件，并有望发现全新的天体物理现象。利用UF的丰富经验，这里概述的项目将利用检测和重建算法，这些算法使用最小的模型假设，并且能够在广泛的源参数范围内检测GW瞬变，包括未知的源。主要的探测目标包括最近发现的中间质量黑洞(IMBH)天体、分级BBH合并和核心塌缩超新星，这些超新星将解决天体物理学中的一些公开问题。建议的活动将把最有希望的GW搜索扩展到现有的基于模板的算法尚未探索的二元参数空间。这些搜索有可能研究IMBH源，约束超新星对不稳定质量间隙，通过探测等级双星来观察星系核内部，并通过将重建的信号波形与数值相对论预测进行比较，实现在强场条件下对广义相对论的精确测试。快速的源重建和天空定位将使电磁望远镜和中微子探测器的联合观测成为可能，从而推动多信使天文学领域的发展。该奖项还支持LIGO O4和O5运行的基线数据分析算法的计划升级，并增加了未来GW观测的科学潜力。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。

This award supports research in relativity and relativistic astrophysics and it addresses the priority areas of NSF's "Windows on the Universe" Big Idea. Gravitational waves (GW), predicted by Albert Einstein’s theory of General Relativity, are the ripples in the fabric of space-time created by relativistic astrophysical systems. Gravitational waves have eluded detection for a hundred years, until 2015, when Advanced LIGO observed GW from two colliding black holes, starting a revolution in the field of multi-messenger astronomy. This detection confirmed a major prediction of General Relativity and opened an unprecedented new window onto the cosmos. Gravitational waves provide a direct probe of complex astrophysical systems. Since 2015, LIGO and its European partner instrument Virgo have reported more than 50 GW events, which are currently under active investigation. Numerous public alerts have been sent to the astronomical community, enabling the multi-messenger observations of those events. In the next few years hundreds of sources are expected to be detected as advanced LIGO reaches its design sensitivity and other instruments join the world-wide network of GW detectors. Even higher detection rates are expected when the LIGO is fully upgraded to its A+ configuration. GW observations will address key research questions including the formation and evolution of black holes and neutron stars, the role of compact objects in the emission of high energy radiation, the properties of nuclear matter, and the nature of gamma-ray-bursts and probe the structure and evolution of the Universe, and, possibly, find physics beyond General Relativity.These research projects will study some of the most extreme astrophysical events and hold a promise for discoveries of entirely new astrophysical phenomena. Leveraging the extensive experience at UF, the projects outlined here will utilize detection and reconstruction algorithms that use minimal model assumptions and that are capable of detecting GW transients in a wide range of the source parameters, including yet unknown sources. Among the primary detection targets are the recently discovered Intermediate-Mass-Black-Hole (IMBH) objects, hierarchical BBH mergers, and the core-collapse supernovae, which will address a number of open questions in astrophysics. The proposed activities will extend the most promising GW searches for compact binary sources into the binary parameter space not explored yet by existing template-based algorithms. These searches have the potential to study the IMBH sources, constrain the supernovae pair instability mass gap, look inside the galactic nuclei by detecting hierarchical binaries and enable precision tests of General Relativity in the strong field regime by comparing the reconstructed signal waveforms with numerical relativity predictions. Rapid source reconstruction and sky localization will enable joint observations with electromagnetic telescopes and neutrino detectors advancing the field of multi-messenger astronomy. This award also supports the planned upgrade of the baseline data analysis algorithms for the LIGO O4 and O5 runs and increases the scientific potential of the future GW observations.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.