Discovering Neutron Stars and Black Holes with LIGO

This award supports research in relativity and relativistic astrophysics, and it addresses the priority areas of NSF's "Windows on the Universe" Big Idea. Discovering Neutron Stars and Black Holes with the NSF's LIGO observatory advances knowledge of the universe through gravitational wave physics and astronomy. Unlike conventional astronomy, which relies on light emitted by distant astronomical sources, gravitational wave astronomy measures tiny ripples in the fabric of space caused by massive objects such as black holes. Therefore, even though a black hole's strong gravity prevents light from escaping its grasp, scientists are able to observe black holes without seeing them. Directly observing the ripples in space from black holes and neutron stars has opened a tremendous potential for physical inferences that were impossible previously. This new field began in 2015 when LIGO observatory detected two black holes crashing together a billion light years away and has since opened a new window on the universe with about one hundred confirmed cosmic collisions. Discovering the tiny ripples of a black hole collision billions of light years away requires sophisticated data analysis. This award funds analysis of LIGO data with the direct goal of detecting hundreds of new black holes and neutron stars in the next three years. These new discoveries will help to reveal how stars are born, how they die, and if the universe has anything hidden in its dark side. The team are committed to making a direct impact through hosting a gravitational wave summer camp in central Pennsylvania. This camp will attract a diverse group of high school students who will have an opportunity to engage with Penn State researchers and learn about gravitational wave physics and astronomy.The projects supported by this award furthers the mission of the LIGO Scientific Collaboration which is focused on the direct detection of gravitational waves, using them to explore the fundamental physics of gravity and developing the emerging field of gravitational wave science as a tool of astronomical discovery. The award will deliver analysis of LIGO data over the next three years resulting in the detection of binary neutron stars, neutron star / black hole binaries and binary black holes. These new gravitational wave detections will comprise the deepest gravitational wave transient catalog to date with potentially hundreds of new discoveries occurring during the period of the proposed work. Each new compact binary merger will provide a new test of General Relativity, and in-aggregate, the discoveries will provide a precise assessment of the population of compact objects in the nearby universe. From this population it may be possible to infer the formation mechanism of the detected binaries and in doing so reveal details about their creation and evolution. With all gravitational wave discoveries, there is an opportunity to observe an electromagnetic or neutrino counterpart. New discoveries of binary neutron star mergers with optical counterparts like GW170817 will, among other things, deepen the understanding of heavy element production as well as to pin down the expansion rate of the universe. The proposed research has substantial inherent opportunities for public engagement as black holes are often met by a captivated audience.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.