A new paper by U²GRC researchers Vijay Varma and Scott E. Field, with collaborators, presents NRSur7dq4v2, an improved surrogate model for gravitational waves from precessing binary black hole mergers.

Numerical-relativity simulations provide highly accurate predictions for these signals, but are too computationally expensive to use directly in many data-analysis applications. The new model divides the waveform into overlapping time domains, allowing the inspiral and merger–ringdown portions to be controlled separately before being combined. This improves estimates of the mass and spin of the remnant black hole, while also extending the modeled modes and improving practical evaluation speed.

The work supports gravitational-wave inference for systems in which the black holes’ spins are misaligned with the orbit—an important setting for interpreting observed binary-black-hole mergers.

Paper: A. Ravishankar, V. Varma, S. E. Field et al., “NRSur7dq4v2: A multi-domain precessing surrogate model with improved accuracy.” arXiv:2609.07873 | INSPIRE