Hybridization of WaSABI-C inspirals with numerical relativity waveforms for quasi-circular, spin-aligned, asymmetric black hole binaries

In recent years the gravitational waveform modeling community has made significant advances in modeling asymmetric, spinning black hole binaries. For instance, the third SXS numerical relativity (NR) catalog of binary black hole simulations includes state-of-the-art simulations at higher mass ratios with moderate spins; and with the release of the WaSABI-C waveform model, a synthesis of first- and second-order gravitational self-force results with high-order post-Newtonian expansions, the dynamics of binaries across a wide range of mass ratios, spins, and orbital separations can be accurately captured. Though each modeling approach has its limitations — NR becoming prohibitively expensive for large mass ratios and long waveform lengths; the WaSABI-C model being restricted to the inspiral stage of the binary evolution — by hybridizing their waveforms we can extend the validity of either approach across parameter space, bridging the gap between NR and perturbative methods. In this talk, I will present NR waveforms hybridized with WaSABI-C inspirals for quasi-circular black hole binary systems in which the black hole spins are aligned or anti-aligned with the orbital angular momentum, and discuss ongoing work towards building a surrogate model trained against these hybrid waveforms. The hybrid waveforms are constructed from a set of spin-aligned, quasi-circular NR waveforms from the SXS catalog with mass ratios spanning 1:1 to 1:20 and primary and secondary spins ranging from -0.8 to 0.8.