Peter James Nee, Adhrit Ravichandran, Scott E. Field, Tousif Islam, Harald P. Pfeiffer, Vijay Varma, Michael Boyle, Andrea Ceja, Noora Ghadiri, Lawrence E. Kidder, Prayush Kumar, Akash Maurya, Marlo Morales, Antoni Ramos-Buades, Abhishek Ravishankar, Katie Rink, Hannes R. Rüter, Mark A. Scheel, Md Arif Shaikh, Daniel Tellez
Mounting evidence indicates that some of the gravitational wave signals observed by ground-based observatories might arise from eccentric compact object binaries, increasing the urgency for accurate waveform models for such systems. While for noneccentric binaries, surrogate models are efficient and accurate, the additional features due to eccentricity have posed a challenge. In this work, we present a method for decomposing eccentric numerical relativity waveforms, making them amenable to surrogate modeling techniques. We parametrize the inspiral in the radial-phase domain, factoring out eccentricity-induced dephasing and thus enhancing compressibility and accuracy. This is combined with a second surrogate for the merger ringdown in the time domain and a technique to take advantage of the approximate periodicity with radial oscillations during the inspiral. We apply this procedure to the (2, 2) mode for nonspinning black hole binaries and demonstrate that the resulting surrogate, , is able to faithfully reproduce the underlying numerical relativity waveforms, with maximum mismatches of 6 × 10 − 4 and median mismatches of 4 × 10 − 5 . This technique paves the way for high-accuracy parameter estimation with eccentric models, a key ingredient for astrophysical inference and tests of general relativity.