NSF Award
2408034
Almost every galaxy has at least one supermassive black hole (SMBH) at its center. These giant black holes can grow to more than 10 billion times the mass of the Sun by pulling in gas and stars and by merging with other black holes. Such mergers rank among the most powerful cosmic events, releasing vast amounts of energy in the form of low-frequency gravitational waves. The gravitational waves produced by SMBH binaries contain clues about the conditions in the hearts of massive galaxies, and they can tell us how the SMBHs have grown over cosmic time. This proposal will enhance the scientific potential of gravitational wave measurements by using computer simulations to see how SMBH binaries interact with their surroundings and by predicting how the host galaxies will appear in ordinary telescopes. The team will start a new outreach program to raise awareness of gravitational wave science, through multi-media simulations of gas moving around black holes. These will be shown at sports events in South Carolina. <br/><br/>The main science objective is to advance the study of binary black holes across the mass spectrum, by providing new paths to their discovery with electromagnetic and gravitational waves. The investigators will carry out numerical simulations of binary-disk interactions in realistic but unexplored regimes. In the context of massive black hole binaries, they will compute the electromagnetic signatures of binary accretion and derive community tools to help optimize time-domain observing strategies and electromagnetically constrain the massive binary black hole population. They will compute the influence of environmental gas on binary evolution and distribute digital tables of the results to support forward modeling of the stochastic gravitational wave background through population synthesis. The team will explore stellar-mass black hole binaries using hydrodynamical simulations to predict how X-ray binaries evolve in response to dynamical mass transfer. Those results will be incorporated into a community binary population synthesis code, and they will help constrain the provenance of stellar-mass black hole and neutron star binaries that merge as high-frequency gravitational wave bursts. This award advances the goals of the NSF Windows on the Universe Big Idea through research in Multi-Messenger Astrophysics.<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.
