During the two year period, this project led to 12 publications, in areas including numerical relativity, surrogate models, and black hole astrophysics.
Notable results include:
1. The first measurement of linear momentum of GWs. We use numerical relativity surrogate models to measure the recoil velocity of the final black hole left behind after a binary black hole merger. Because the binary radiates away linear momentum in preferred directions, the final black hole is imparted a recoil in the opposite direction. Measuring such a recoil has important implications like understanding how heavy stellar mass black holes form in nature, because if the recoils are large enough the final black hole would get ejected from its host galaxy rather than forming even heavier black holes through repeated mergers. This work resulted in the publication Physical Review Letters, 128, 191102 (2022), which was featured as an Editors Suggestion and received wide media coverage, for example, in news outlets like New Scientist, Discover Magazine, Science News, etc.
2. The first numerical simulations of black hole neutron star mergers in scalar tensor gravity. Such simulations are vital for providing predictions for the expected gravitational waves based on alternative theories of gravity. Given such predictions one can compare directly with observations to try and determine if alternative theories better fit the data than Einstein's general relativity. This work led to the publication Physical Review D, 107, 124051 (2023).
