Gravitational Wave Astrophysics with LIGO: The Oregon Experimental Relativity Group

University Of Oregon Eugene, Eugene OR

Investigators

Abstract

This award supports research in gravitational wave detector commissioning and characterization, as well as data analysis and it addresses the priority areas of NSF's "Windows on the Universe" Big Idea. A Search for Gravitational Radiation at LIGO Oregon Experimental Relativity Group. With the discovery of gravitational waves in September 2015 via the observation a merger of black holes, and the birth of multi-messenger astrophysics with gravitational waves in 2017 via the observation of a merger of neutron stars, the LIGO collaboration has become a key player in 21st century science in the areas of fundamental physics, astronomy, astrophysics, and cosmology. Because the LIGO detectors measure such tiny perturbations in spacetime -- distances 10,000 smaller than the diameter of a proton -- it is extremely sensitive to environmental disturbances, such as ground motion or background magnetic fields. During the period of this award, the LIGO instruments will be even more sensitive, meaning that the rate of detections of known astrophysical sources will be increased, and new, previously unobserved sources may appear. With this award, the group will develop the expertise and toolkits needed to meet the data quality and analysis challenges provided by the enhanced LIGO instruments. The team's graduate students will continue to play a critical role in these developments. The team will give public presentations on these exciting developments. This includes the organization of a yearly workshop for Oregon high school science teachers, so that they can convey the latest findings to their students. The team will further develop the ability to characterize the coupling of relevant environmental disturbances to gravitational-wave data. The greater sensitivity of the detectors, along with the associated higher detection rates make these developments imperative. The team has developed software to determine potential environmental contamination levels to gravitational wave candidates in low latency. This is provided in the data quality reports made available for immediate evaluation for the O3 open public alerts. These tools are fairly rudimentary and further development will be needed to achieve the goal of a fully automatized process which is reliable and accurate. Continued improvement of the instrumentation and delivery of environmental injections will be needed to keep pace with the improved sensitivity of the LIGO interferometers. Graduate students will undertake environmental injection studies and associated data analyses, as well as gravitational wave astrophysics projects, covering the topics of GRBs, magnetar flares, and supernovae. While refinements will be needed for these studies to keep pace with the improved LIGO sensitivities and better astrophysical understanding of the sources, in some cases new techniques will be needed. One example for this is for the so-called sub-threshold GRBs. The need for this was spectacularly illustrated with GRB/GW170817. 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.