Fast post-adiabatic waveforms in the time domain: Applications to compact binary coalescences in LIGO and Virgo

TL;DR

This paper introduces a fast, accurate time-domain waveform model for compact binary coalescences, significantly reducing computational costs while maintaining high fidelity, enabling efficient parameter estimation and tests of gravity.

Contribution

The authors develop a novel multipolar waveform model combining EOB and post-adiabatic methods, achieving 10-100x speed improvements over existing models.

Findings

Speed-up of 10-100 times compared to traditional EOB models.

Unfaithfulness less than 0.01% across parameter space.

Successful application to parameter estimation and GR tests.

Abstract

We present a computationally efficient (time-domain) multipolar waveform model for quasi-circular spin-aligned compact binary coalescences. The model combines the advantages of the numerical-relativity informed, effective-one-body (EOB) family of models with a post-adiabatic solution of the equations of motion for the inspiral part of the two-body dynamics. We benchmark this model against other state-of-the-art waveforms in terms of efficiency and accuracy. We find a speed-up of one to two orders of magnitude compared to the underlying time-domain EOB model for the total mass range $2 - 100 M_{\odot}$. More specifically, for a low total-mass system, such as a binary neutron star with equal masses of $1.4 M_{\odot}$, like GW170817, the computational speedup is around 100 times; for an event with total mass $\sim 40 M_\odot$ and mass ratio $\sim 3$, like GW190412, the speedup is by a factor of $\sim 20$, while for a binary system of comparable masses and total mass of $\sim 70 M_{\odot}$, like GW150914, it is by a factor of $\sim 10$. We demonstrate that the new model is extremely faithful to the underlying EOB model with unfaithfulness less than $0.01\%$ across the entire applicable region of parameter space. Finally, we present successful applications of this new waveform model to parameter estimation studies and tests of general relativity.