CAREER: Research and Education in Gravitational-Wave Science

2015年由NSF资助的激光干涉引力波天文台（LIGO）探测到的引力波证实了爱因斯坦广义相对论的最后一个预测，并开辟了观测天文学和基础物理学的新时代。LIGO及其国际合作伙伴未来的观测将发现更多的黑洞对。这些观测将帮助我们理解这些系统是如何形成的，并让我们在这些合并黑洞产生的超强引力区域中测试广义相对论。这里资助的工作主要涉及：（i）提高我们模拟LIGO将从黑洞合并中检测到的信号的能力;（ii）开发模拟和检测引力波信号分量的技术，这些技术可以揭示引力的非线性性质，超新星喷射的物质和能量，或经历近距离飞越的致密恒星的动力学;以及（iii）探索下一代引力波实验可以实现的科学目标。这项工作的教育部分包括：（一）在具有广泛社会经济背景的地区公立大学培训本科生和硕士生;（二）编写和提供教授LIGO科学的教学材料和实践工具包; ㈢通过讲座、外联展览，以及“时空之声”网站的持续发展（通过与声波的类比来解释引力波科学）。这项工作的科学目标集中在（一）改进合并椭圆（偏心）轨道双星系统的模型和（二）引力波记忆效应。 椭圆双星：LIGO目前有许多信号模型来分析圆轨道双星，但很少有椭圆双星。该小组将开发新的信号模型来处理偏心轨道，并研究参数估计和测试广义相对论的含义。如果LIGO信号中存在偏心率，偏心率将对紧凑物体二元形成模型产生影响，并限制广义相对论的可能偏差（如果忽略偏心率，可能会有偏差）。记忆效应：记忆效应是指引力波信号的非振荡成分。它是由引力二体散射、超新星中的喷射物质或中微子以及黑洞合并过程中的非线性相互作用产生的。这一努力将改善记忆效应的现有模型。它还将开发，测试和执行使用LIGO数据的内存突发搜索。这将扩大LIGO研究的信号类别，并可能为测试广义相对论提供新的方法。

The detections of gravitational waves in 2015 by the NSF-funded Laser Interferometer Gravitational-wave Observatory (LIGO) have confirmed the last prediction of Einstein's theory of general relativity and opened up a new era in observational astronomy and fundamental physics. Future observations by LIGO and its international partners will discover many more merging black hole pairs. These observations will help us understand how these systems formed and will let us test general relativity in the ultra-strong gravity region produced by these coalescing black holes. The work funded here is primarily concerned with: (i) improving our ability to model the signals LIGO will detect from black hole mergers; (ii) developing techniques to model and detect a component of gravitational-wave signals that can shed light on the nonlinear nature of gravity, the matter and energy ejected by supernovae, or the dynamics of compact stars that experience close flybys; and (iii) exploring science objectives that could be achieved by the next generation of gravitational-wave experiments. The educational components of this work include: (i) training undergraduate and master's degree students at a regional public university serving a wide range of socio-economic backgrounds; (ii) developing and making available instructional materials and hands-on kits that teach LIGO science; (iii) engaging the broader public through lectures, outreach exhibits, and the continued development of the "Sounds of Spacetime" website (which explains gravitational-wave science via an analogy with sound waves). The science objectives of this work are focused on (i) improving models of merging binary systems with elliptical (eccentric) orbits and (ii) the gravitational-wave memory effect. Elliptical binaries: LIGO currently has many signal models to analyze circular-orbit binaries, but few for elliptical binaries. The group will develop new signal models to handle eccentric orbits and investigate the implications for parameter estimation and testing general relativity. If present in LIGO signals, eccentricity will have implications for compact object binary formation models and constraining possible deviations from general relativity (which could be biased if eccentricity is neglected). Memory effect: The memory effect refers to a non-oscillatory component of the gravitational-wave signal. It is produced by gravitational two-body scattering, ejected matter or neutrinos in supernovae, and nonlinear interactions during black hole mergers. The effort will improve existing models of the memory effect. It will also develop, test, and execute a search for memory bursts using LIGO data. This will broaden the class of signals that LIGO investigates and could provide a new way to test general relativity.