Surrogate model of gravitational waveforms for quasi-circular, spin-aligned, asymmetric-mass black hole binaries based on the hybridization of WaSABI-C inspirals with numerical relativity waveforms

Abstract

With the incorporation of aligned-spin dynamics into self-force waveform models, such as the WaSABI-C inspiral model, and with the release of the SXS collaboration's third public catalog of NR simulations, the gravitational waveform modeling community has made significant advances in the modeling of spinning, asymmetric-mass black hole binaries. In light of these developments, we present WaSABINRHybSur2dq15, the first surrogate model to incorporate information from self-force theory, post-Newtonian theory, and numerical relativity. The model is trained on 65 hybrid waveforms for quasi-circular, spin-aligned, asymmetric-mass black hole binaries with mass ratios spanning 1:1.25 to 1:20 and aligned-spins for the primary black hole ranging -0.5 to 0.5. The hybrid waveforms are generated from a set of WaSABI-C inspirals and NR waveforms from the third SXS public catalog. The model covers the parameter domain $1.25 \leq q \leq 15$ and $|χ_{1z}| \leq 0.5$, and includes the $(2,2),\, (2,1),\, (3,3),\, (4,4),$ and $(5,5)$ spin-weighted spherical harmonic modes. The model also spans the entire LIGO-Virgo-KAGRA (LVK) frequency band (with $f_{\text{low}}=20$ Hz) for total masses $M \gtrsim 111.5\,M_{\odot}$. We find that the WaSABINRHybSur2dq15 model faithfully reproduces the hybrid waveforms with mismatches less than $10^{-3}$ for total masses in the range $80\,M_{\odot} \leq M \leq 300\,M_{\odot}$.