PIRE: An International Pulsar Timing Array for Gravitational Wave Detection

该PERER奖将建立一个利用毫秒脉冲星(MSPS)的定时观测来探测和研究低频引力波(GWS)的国际团队。GW是时空结构中的涟漪，由加速运动中的大质量物体发出。MSP是一种快速旋转的高磁中子星，它发出无线电波脉冲--类似于灯塔的闪光--GWS扰乱了这些脉冲从脉冲星到地球的传播。与他们的国际合作者一起，美国研究人员和学生将使用射电望远镜在几年内观测来自数十颗脉冲星的信号。这将使PERE团队能够直接测试GWS的存在，并在检测到后，测量它们的天空分布、偏振和光谱，并识别和表征它们的天体物理来源。GW是爱因斯坦广义相对论的关键预测，广义相对论是对引力和时空最完整的描述，但到目前为止，只有间接证据表明它们的存在。直接探测GWS是天体物理学最具变革性的前景之一，它有可能通过研究大质量星系内的黑洞和宇宙早期阶段的时空动力学来彻底改变我们对宇宙的认识。国际合作和协调使用全球资源对于探测低频引力波至关重要。脉冲星被监测的时间越长，探测灵敏度就越高，因此需要多年的观测。成对的MSP必须从地球上遥远的点进行观测，以最大限度地提高灵敏度，因此需要在两个半球都有观测地点。此外，为了获得高精度，需要在许多无线电观测频率上进行长时间、频繁的观测，并且必须对尽可能多的MSP进行观测。所有这些因素加在一起，对世界射电望远镜的时间提出了巨大的需求。该PERE项目将促进北美引力波纳赫兹天文台(NANOGrav)与澳大利亚、欧洲和印度科学家之间的国际脉冲星定时阵列(IPTA)伙伴关系，并将集中精力开展具有专门研究能力的GW探测工作。通过将在世界上最好的设施中获取的数据与最高精度的检测技术相结合，以及来自世界各地的专家，帝国团队希望在5-10年内检测出GWS。这一国际项目将有助于建立一支更加多元化、全球参与的美国科学和工程劳动力队伍。它将培养第一代能够直接观测和研究全球观测系统的天文学家，并将为美国初级参与者培养成为这一新领域未来的领导者。他们将获得脉冲星计时所需的关键技术技能，并将探索此类测量对天体物理学基础的影响。该项目将支持9个美国机构的博士后研究人员以及研究生和本科生，每年举行的国际科学会议、学生研讨会以及研究和观察旅行。当学生和研究人员在望远镜设施上进行观测时，他们将有助于在不同的教育水平、机构和国家之间建立一个国际指导网络。该项目还将利用世界上最好的射电望远镜可以对望远镜进行远程观测和控制的事实，从而提供一种让更多的本科生和高中生参与该项目的方法。该项目将加强美国机构的能力，使其研究、科学网络和课程国际化。这一重大努力将扩大美国机构的虚拟国际影响力，因为它们的教职员工和学生使用网络基础设施访问和分析来自世界各地的数据，远程操作望远镜，通过社交网络工具分享经验，并主办国际教程和基于网络的研讨会。这些美国机构是汇集北美资源的NANOGrav财团的成员，该项目将进一步巩固它们在美国和国际上的联系。美国机构包括：康奈尔大学(NY)，德克萨斯大学布朗斯维尔分校，富兰克林和马歇尔学院(PA)，西弗吉尼亚大学，布林莫尔学院(PA)，佛蒙特大学，国家射电天文台(VA)，威斯康星大学密尔沃基分校，奥伯林学院(OH)，大学空间研究协会和AMP；外国机构包括：斯温本大学(澳大利亚)、L在巴黎南塞/南沙天文台的观测台(法国)、波恩大学的马克斯·普朗克射电天文学研究所(MPIfR)(德国)、国家射电天体物理中心(NCRA)(印度)、荷兰射电天文学研究所(ASTRON)、澳大利亚望远镜国家设施(ATNF)、麦吉尔大学(加拿大)、莱顿大学(荷兰)、曼彻斯特大学(英国)、Osservatorio Astronomico di Cagliari(意大利)该项目由美国国家科学基金会国际科学与工程办公室和天文科学部共同资助。

This PIRE award will establish an international team for the detection and study of low frequency gravitational waves (GWs) using timing observations of millisecond pulsars (MSPs). GWs are ripples in the fabric of spacetime that emanate from massive objects in accelerated motion. MSPs are rapidly rotating highly magnetic neutron stars that emit pulses of radio waves - similar to flashes of light from a lighthouse - and GWs perturb the travel of these pulses from a pulsar to the Earth. Together with their international collaborators, U.S. researchers and students will use radio telescopes to observe signals from dozens of pulsars over several years. This will enable the PIRE team to directly test for the existence of GWs and, after detection, measure their sky distribution, polarization, and spectrum and identify and characterize their astrophysical sources. GWs are a key prediction of Einstein's theory of general relativity - the most complete description of gravity and spacetime - but until now only indirect evidence has pointed to their existence. Direct detection of GWs is one of the most transformational prospects of astrophysics, with the potential to revolutionize our knowledge of the universe by enabling studies of black holes within massive galaxies and the spacetime dynamics of early stages of the universe. Both international collaboration and coordinated use of worldwide resources are critical for detecting low frequency gravitational waves. Detection sensitivity increases the longer the pulsars are monitored, so observations over many years are required. Pairs of MSPs must be observed from far distant points on earth to maximize sensitivity, thus requiring observing sites in both hemispheres. Additionally, long, frequent observations across many radio observing frequencies are required for high precision and must be done for as many MSPs as possible. All of these factors combine to place a substantial demand on the world's radio telescope time. This PIRE project will catalyze the International Pulsar Timing Array (IPTA) partnership between the North American NanoHertz Observatory for Gravitational waves (NANOGrav) and Australian, European, and Indian scientists and will focus a coordinated effort with dedicated research power on GW detection. By combining data taken at the world's best facilities, with the highest-precision detection techniques, with experts from around the world, the PIRE team expects to detect GWs within the 5-10 years. This international project will contribute to a more diverse, globally-engaged, U.S. science and engineering workforce. It will train the first generation of astronomers able to directly observe and study GWs and will prepare U.S. junior participants to be the future leaders of this new field. They will gain the vital technical skills needed for pulsar timing and will also explore the impacts of such measurements on the fundamentals of astrophysics. The project will support postdoctoral researchers and graduate and undergraduate students at nine U.S. institutions, yearly international science meetings, student workshops, and research and observing trips. As students and researchers make observations at the telescope facilities, they will help to build an international mentoring network amongst different educational levels, institutions, and countries. The project will also exploit the fact that the world's best radio telescopes allow remote observing and control of the telescope, thus providing a way to involve more undergraduate and high school students in the project.The project will strengthen the capacity of the U.S. institutions to internationalize their research, scientific networks, and curricula. This PIRE effort will broaden the virtual international reach of U.S. institutions as their faculty and students use cyberinfrastructure to access and analyze data from around the world, operate telescopes remotely, share experiences via social networking tools, and host international tutorials and web-based seminars. The U.S. institutions are members of the NANOGrav consortium that pools North American resources and this project will further solidify their U.S. and international linkages. Finally, once established, a consortium-wide Memorandum of Understanding (MOU) for the planned research/study abroad programs will continue to provide valuable opportunities for current and future generations of students at these institutions.U.S. institutions include: Cornell University (NY), University of Texas at Brownsville, Franklin and Marshall College (PA), West Virginia University, Bryn Mawr College (PA), University of Vermont, National Radio Astronomy Observatory (NRAO) (VA), University of Wisconsin at Milwaukee, Oberlin College (OH), Universities Space Research Association & NASA Goddard Space Flight Center (MD), National Astronomy and Ionosphere Center (PR), and the Naval Research Laboratory (D.C.).Foreign institutions include: Swinburne University (Australia), L'Observatoire de Paris at Nançay/Nançay Observatory (France), Max Planck Institute for Radio Astronomy (MPIfR) at the University of Bonn (Germany), National Center for Radio Astrophysics (NCRA) (India), Netherlands Institute for Radio Astronomy (ASTRON), Australia Telescope National Facility (ATNF), McGill University (Canada), Leiden University (The Netherlands), University of Manchester (UK), Osservatorio Astronomico di Cagliari (Italy), and University of British Columbia (Canada).This PIRE project was cofunded by NSF's Office of International Science and Engineering and the Division of Astronomical Sciences.