AccelNet-Implementation: The International Pulsar Timing Array

West Virginia University Research Corporation, Morgantown WV

Investigators

Abstract

Gravitational waves are ripples in spacetime, predicted to exist by Einstein's theory of general relativity. They are emitted by accelerating, massive objects and travel at the speed of light, unimpeded by matter such as galaxies, stars, and gas. Gravitational waves from the merger of two black holes were detected by the LIGO collaboration in 2015, allowing astronomers to "see" previously invisible objects and probe the most energetic processes in the universe. The International Pulsar Timing Array (IPTA) is a world-wide network of researchers and students working to directly detect gravitational at frequencies 11 orders of magnitude smaller than LIGO through observations of precise celestial clocks called radio pulsars using the world's largest radio telescopes. This AccelNet-Implementation project will broaden the reach of the IPTA beyond researchers and students from North America, Europe, and Australia to include China, India, and South Africa. In addition to enhancing observations of pulsars distributed across the sky, the expanded IPTA network will provide sophisticated cyber-infrastructure and training for students and postdoctoral researchers in astrophysics, radio instrumentation, signal processing, and data science. The IPTA expects to detect gravitational waves from supermassive binary black holes at the cores of merging galaxies. These detections will provide new insights into galaxy growth and evolution through cosmic time, transforming our understanding of the Universe. By the end of the award period, the IPTA will detect and characterize the stochastic background of gravitational waves produced by all the supermassive binary black holes in the Universe. It is also likely to detect the first individual supermassive black hole binary that stands out above the background. This international coordination of research will also result in very high impact synergistic science such as neutron star mass measurements, characterization of the interstellar medium, tests of general relativity, and the discovery of exotic pulsar systems and radio transients such as Fast Radio Bursts. Coordination will be facilitated through annual workshops, meetings, and shared data and analysis portal. Students and postdoctoral researchers in the IPTA will be involved in an international mentoring network and will learn valuable outreach skills, while at the same time bringing the excitement of this work to K-12 students worldwide. The Accelerating Research through International Network-to-Network Collaborations (AccelNet) program is designed to accelerate the process of scientific discovery and prepare the next generation of U.S. researchers for multiteam international collaborations. The AccelNet program supports strategic linkages among U.S. research networks and complementary networks abroad that will leverage research and educational resources to tackle grand scientific challenges that require significant coordinated international efforts. 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.