Simulating Black Hole-Neutron Star Mergers

Gravitational waves are ripples in space and time predicted by Einstein’s theory of relativity; in 2015, Advanced LIGO observed these waves passing through Earth for the first time. We hope to observe black hole-neutron star (BHNS) mergers for they are “multi-messengers,” emitting both electromagnetic and gravitational waves. Highly accurate descriptions of these waves are crucial for helping experiments to detect gravitational waves from BHNS mergers. Using the Spectral Einstein Code, we are modeling BHNS mergers for different binaries, computing emitted gravitational waves, properties of the black hole before, during, and after the merger, and behaviors of the neutron-star matter as it is torn apart. So far, we have focused on low-mass mergers with non-spinning black holes, a case where tidal effects on the emitted gravitational waves are especially strong. In the future, we will extend this work to rapidly spinning merging black holes.