NSF Award
2409448
NSF’s LIGO observatories have produced outstanding scientific discoveries, including the first direct detection of gravitational waves in 2015, a spectacular “multi-messenger” astronomical event in 2017, and many tests of Albert Einstein’s general theory of relativity. The LIGO observatories have been improved and more data has been collected, now coordinated with the Virgo observatory in Europe and the KAGRA observatory in Japan. As of mid-2024, about 200 significant gravitational-wave events have been detected. The vast majority of those have been from merging black holes with masses up to about 80 times the mass of our Sun. This award supports two special projects seeking new types of gravitational-wave signals that may be hiding in LIGO-Virgo-KAGRA (LVK) data. The first project aims to detect merging black holes much heavier than any seen so far, using more accurate signal models that include higher frequency components. The second project is to search for gravitational waves from rapidly spinning neutron stars which have been identified as gamma-ray pulsars by NASA’s Fermi Gamma-ray Space Telescope mission, but which are not currently included in LIGO-Virgo-KAGRA searches. Both projects have technical challenges that must be overcome and will be led by graduate students, who will gain scientific expertise and analysis skills while supported by this award. Either project could also lead to the next big gravitational wave discovery, expanding our knowledge of compact stars and black holes in the Universe. This award also supports observing operations including real-time data analysis and rapid checks so that reliable candidate events can be quickly communicated to astronomers, to enable rapid follow-up observations of new multi-messenger events. It also supports publishing a wide range of LIGO-Virgo-KAGRA science results along with outreach and engagement, sharing scientific research concepts and results with high-school students and the general public.<br/><br/>This award supports a research program with multiple goals: to expand the gravitational-wave (GW) discovery space by developing searches for distinctive signals that are not being adequately covered by current LVK collaboration searches; to maintain and optimize low-latency searches and rapid response so that astronomers have the best chance to catch and study multi-messenger GW events; and to ensure that GW science results are published and shared with the public, including students. Two grad-student-led projects address the first goal. In one project, the PyCBC data analysis pipeline will be adapted to use templates calculated from the SEOBNRv5PHM waveform model, with a total mass between 100 and 1500 solar masses and a mass range of up to 20. The template bank will be constructed using stochastic methods. The plus and cross polarizations, including higher-order modes, will be stored and filtered separately, and a non-parametric model of the noise will be developed to optimize the search efficiency for short, broadband signals. The second project will target continuous-wave GW emissions from pulsars in the Third Fermi-LAT Catalog of Gamma-ray Pulsars (3PC). Different gamma-ray emission models will be used to perform a population analysis of the pulsars in 3PC which are currently included in LVK targeted searches, using the CWInPy software package. The available timing information for other pulsars in 3PC will be studied to determine which ones are suitable for additional time-domain targeted searches using LVK data and CWInPy. Either of these projects could lead to a breakthrough discovery of a currently unseen GW source. Addressing the second goal, this award supports the maintenance, optimization, and operation of the PyCBC Live software for low-latency searches during the O4 observing run, real-time monitoring and rapid response team handling of GW event candidates, and preparations for the future O5 run. Addressing the third goal, it supports contributions to producing specific LVK papers as well as the maintenance of collaboration software tools to plan, track, and publish the LVK’s science results. It also supports sharing scientific research concepts and results with school-age students through direct engagement and with the general public through online summaries of scientific findings.<br/><br/>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.
