The NANOGrav Physics Frontiers Center

这个物理前沿中心（PFC）奖给北美纳赫兹引力波天文台（NANOGrav）支持他们专注于直接探测和表征低频引力波（GW），在纳赫兹制度，大约11个数量级小于GW已经探测到的激光干涉仪引力波天文台（LIGO）;这两个NSF支持的实验是高度互补的。 NANOGrav通过监测毫秒双星（MSP）的脉冲到达时间来进行这项研究，MSP是超自旋稳定的中子星，因此是宇宙中最精确的天体时钟。 GW引起脉冲到达时间的波动，这些波动在不同的雷达之间是相关的。 发现这些相关性需要引力物理学、数据分析和天体物理学专家在协作环境中的协同作用。 除了监测已知的MSP列表外，NANOGrav还定期发现新的MSP以添加到他们的研究中。 NANOGrav通过展览和讲座以及不断增长的社交媒体影响力吸引了大量公众。 每年有超过150名本科生参与相关的学生研究计划，脉冲星搜索合作实验室（Pulsar Search Collaboratory）则有数百名初高中学生和他们的老师参与。在不久的将来，在纳赫兹波段最有可能被探测到的来源是超大质量双黑洞，它们是大质量星系合并后形成的。 事实上，到目前为止，NANOGrav搜索已经对星系及其超大质量黑洞的演化进行了天体物理学上有趣的限制。 其他来源包括宇宙弦，早期宇宙的相变，以及暴胀产生的残留GW;检测任何这些都将是变革性的。 GW观测还可以用来研究宇宙加速的起源以及量子力学和广义相对论之间的冲突，这是基础物理学目前面临的两个最深刻的挑战。 除了GW，NANOGrav观测还可以实现高影响力的协同科学，包括约束稠密物质状态方程，对广义相对论进行动力学测试，进一步了解电离星际介质，和发现奇异的中子星星系统和无线电瞬变。这个物理前沿中心奖是由物理学部的物理前沿中心计划和美国中期研究所共同资助的。天文科学部的规模创新计划。 该项目推进了NSF宇宙大创意窗口的目标。该奖项反映了NSF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。

This Physics Frontiers Centers (PFC) award to the North American Nanohertz Observatory for Gravitational Waves (NANOGrav) supports their focus on the direct detection and characterization of low-frequency gravitational waves (GW), in the nanohertz regime, some eleven orders of magnitude smaller than the GW already detected by the Laser Interferometer Gravitational-wave Observatory (LIGO); these two NSF-supported experiments are highly complementary. NANOGrav carries out this study by monitoring the pulse arrival times of millisecond pulsars (MSPs), which are ultra-spin-stable neutron stars, and thus the most precise celestial clocks in the Universe. GWs cause fluctuations in pulse arrival times that are correlated among different pulsars. Discovering these correlations requires the synergy of experts in gravitational physics, data analysis, and astrophysics coming together in a collaborative environment. In addition to monitoring a known list of MSPs, NANOGrav routinely discovers new MSPs to add to their study. NANOGrav reaches large numbers of the general public through exhibits and talks, and a growing social media presence. An associated student research program reaches more than 150 undergraduate students every year, and the Pulsar Search Collaboratory involves hundreds of middle and high school students and their teachers.The sources most likely to be detected in the nanohertz band in the near future are supermassive binary black holes that form after massive galaxies merge. In fact, NANOGrav searches so far have already placed astrophysically interesting constraints on the evolution of galaxies and their supermassive black holes. Other sources include cosmic strings, phase transitions in the early universe, and relic GW from inflation; detecting any of these would be transformative. GW observations can also be used to investigate the origin of cosmic acceleration and the conflict between quantum mechanics and general relativity, two of the most profound challenges currently facing fundamental physics. Apart from GW, NANOGrav observations enable high-impact synergistic science, including constraining the dense matter equation of state, making dynamical tests of general relativity, further understanding the ionized interstellar medium, and discovering exotic neutron star systems and radio transients.This Physics Frontiers Centers award is co-funded by the Physics Frontiers Centers Program in the Division of Physics and the Mid-scale Innovations Program in the Division of Astronomical Sciences. This project advances the goals of the NSF Windows on the Universe Big Idea.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.