From First Detections to Gravitational-Wave Astrophysics

2015年9月14日，LIGO首次探测到引力波。这些波是时空结构中的涟漪，一个世纪前爱因斯坦最先预测了它们。LIGO探测到的波是两个黑洞灾难性碰撞的结果，每个黑洞的质量都是我们太阳的30倍，它们以一半光速相撞。引力波的探测为我们探索宇宙开辟了一条全新的道路。我们将学习宇宙中最早的恒星，黄金等元素是如何在宇宙中形成的，我们还将测试爱因斯坦的引力理论(物理学的基本支柱)。这个项目是为了帮助发展这一全新的引力波天体物理领域，并探索LIGO将教会我们什么关于天体物理和宇宙学。这个项目的第一个主要主题是LIGO天体物理。在不久的将来，有趣的LIGO约束将来自统计分析，而不是个别事件。例如，我们可以预测三个感兴趣的一般天体物理量：1.紧凑双星系统的合并速率，2.这些合并的质量和质量比分布，以及3.组成系统的自旋分布。PI将帮助产生这些分布和随之而来的科学。这项工作是引力波天体物理学领域的核心。除了这项核心工作外，PI还将参与许多相关项目，包括分层形成通道中的自旋建模、使用高斯过程仿真器对致密双星聚合的波形进行建模、LIGO天体物理中系统误差的作用，以及LIGO约束电磁带电黑洞的能力。该项目的第二个主要主题是多信使天文学，重点是下一次引力波革命：识别引力波来源的电磁对应物。这将阐明潜在的天体物理过程，并阐明这些引力波事件的形成通道。此外，多信使天文学提供了将引力波源用作标准蜡烛来约束宇宙学的可能性。国际和平研究所计划开发工具和管道，以加速引力波多信使天文学的到来，包括通过继续改进和实施低延迟3D定位算法和优化后续资源分配，促进电磁后续工作。该项目将帮助LIGO发挥其作为天文天文台的巨大潜力。

On September 14, 2015, LIGO detected gravitational waves for the very first time ever. These waves are ripples in the fabric of spacetime, and were first predicted by Einstein a century ago. The waves that LIGO detected were the result of a cataclysmic collision of two black holes, each 30 times more massive than our own Sun, crashing into each other at half the speed of light. This detection of gravitational waves has opened up an entirely new way for us to explore our Universe. We will learn about the very first stars in the Universe, how elements such as gold were made in the Universe, and we will also test Einstein's theory of gravity (a fundamental pillar of physics). This project is to help develop this entirely new field of gravitational-wave astrophysics, and to explore what LIGO will teach us about astrophysics and cosmology.The first major theme of this project is LIGO Astrophysics. In the near future interesting LIGO constraints will arise from statistical analyses rather than individual events. For example, we can anticipate three general astrophysical quantities of interest: 1. the rate of mergers of compact binary systems, 2. the mass and mass ratio distributions of these mergers, and 3. the spin distributions of the component systems. The PI will help produce these distributions and the attendant science. This work is at the heart of the field of gravitational-wave astrophysics. In addition to this core work, the PI will engage in a number of related projects, including the modeling of spins in hierarchical formation channels, the use of Gaussian Process Emulators to model waveforms from compact binary coalescence, the role of systematic errors in LIGO astrophysics, and LIGO's ability to constrain electromagnetically charged black holes. The second major theme of the project is Multi-Messenger Astronomy, which focuses on the next gravitational-wave revolution: identifying electromagnetic counterparts to gravitational-wave sources. This will shed light on the underlying astrophysical processes and elucidate the formation channels of these gravitational-wave events. In addition, multi-messenger astronomy offers the potential to use gravitational-wave sources as standard candles to constrain cosmology. The PI plans the development of tools and pipelines to hasten the arrival of gravitational-wave multi-messenger astronomy, including facilitating electromagnetic follow-up efforts through the continuing refinement and implementation of low-latency 3D localization algorithms and the optimization of follow-up resource allocation. This project will help LIGO reach its tremendous potential as an astronomical observatory.