NANOGrav Physics Frontier Center

广义相对论预言了引力波的存在，但还没有直接探测到。除了测试广义相对论，引力波的发现还将使对解释宇宙膨胀加速的起源以及量子力学与引力相一致的理论的新测试成为可能，这是基础物理、天体物理和宇宙学面临的两个最深刻的挑战。通过这一物理前沿中心(PFC)奖，北美纳赫兹引力波天文台(NANOGrav)将专注于探测和表征纳赫兹频率的引力波--频率比激光干涉仪引力波天文台探测到的频率低11个数量级。NANOGrav将利用对毫秒脉冲星(以毫秒量级的周期旋转的脉动中子星)的观测来搜索这些低频波。如果引力波的传播扭曲了这些脉冲星的辐射，它们的到达时间将偏离它们的正常模式。将不同脉冲星之间的观测与监测脉冲到达时间相关联，将使NANOGrav能够以一种与LIGO不同但互补的方式搜索这些低频引力波。NANOGrav还将让中学生和本科生参与他们的研究工作，包括数据收集、分析和表征，以及在数据中搜索引力波。NANOGrav物理前沿中心将监测毫秒脉冲星(MSP)的脉冲到达时间，以探测和表征低频引力波(GWS)。除了已知的MSP外，该中心还将寻找新的MSP。研究目标和活动涉及：探测和描述低频GW，包括算法开发、研究GW源的电磁对应关系和GW重力测试；创建和管理GW数据集，包括创建为搜索GW而分析的时间序列，充分描述数据集及其误差预算，创建新的独立软件包以创建GW数据集，以及数据挖掘和分发；以及通过增加探测臂的数量、表征脉冲星并开发算法来提高他们搜索新MSP的效率，从而进一步增强和表征他们的低频GW探测方法。该物理前沿中心奖由物理系的物理前沿中心计划和天文科学部的中等规模创新计划共同资助。

General Relativity predicts the existence of gravitational waves, but none have yet been directly detected. In addition to testing General Relativity, the discovery of gravitational waves will make possible new tests of theories that explain the origin of the acceleration of the universe's expansion and that reconcile quantum mechanics with gravity, two of the most profound challenges facing fundamental physics, astrophysics, and cosmology. Through this Physics Frontiers Centers (PFC) award the North American Nanohertz Observatory for Gravitational Waves (NANOGrav) will focus on the detection and characterization of gravitational waves with nanohertz frequencies-frequencies eleven orders of magnitude lower than those probed by the Laser Interferometer Gravitational-Wave Observatory (LIGO). NANOGrav will use observations of millisecond pulsars (pulsating neutron stars spinning with a period on the order of a millisecond) to search for these low frequency waves. The arrival times of the emissions from these pulsars will stray from their regular pattern if distorted by the passage of a gravitational wave. Correlating observations between different pulsars and monitoring pulse arrival times will enable NANOGrav to search for these low frequency gravitational waves in a way different from but complementary to LIGO. NANOGrav will also engage middle school and undergraduate students in their research efforts, including data collection, analysis, and characterization, as well as the search for gravitational waves in the data. The Center will have a targeted approach to increase student participation of women and traditionally underrepresented groups.The NANOGrav Physics Frontier Center will monitor the pulse arrival times of millisecond pulsars (MSPs) in order to detect and characterize low frequency gravitational waves (GWs). In addition to known MSPs, the Center will search for new ones. Research goals and activities involve: the detection and characterization of low frequency GWs, including algorithm development, the study of electromagnetic counterparts to GW sources, and GW tests of gravity; the creation and curation of a GW dataset, including the creation of the time series analyzed to search for GWs, full characterization of the data set and its error budget, creation of a new, independent software package to create the GW data sets, as well as data mining and distribution; and the further enhancement and characterization of their low frequency GW detection method with increased sensitivity resulting from adding to the number of detection arms, characterizing their pulsars, and developing algorithms to increase the efficiency of their searches for new MSPs.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.