Modeling multipolar gravitational-wave emission from small mass-ratio mergers

TL;DR

This paper combines the effective-one-body formalism with a Teukolsky code to generate accurate gravitational waveforms for small mass-ratio black hole mergers, improving existing models for various modes.

Contribution

It introduces a method to generate full coalescence waveforms using EOB trajectories and Teukolsky equations, enhancing the accuracy of waveform models for spinning black hole binaries.

Findings

Improved EOB waveform models for multiple modes.

Accurate waveforms for a range of black hole spins.

Enhanced tools for gravitational wave data analysis.

Abstract

Using the effective-one-body (EOB) formalism and a time-domain Teukolsky code, we generate inspiral, merger, and ringdown waveforms in the small mass-ratio limit. We use EOB inspiral and plunge trajectories to build the Teukolsky equation source term, and compute full coalescence waveforms for a range of black hole spins. By comparing EOB waveforms that were recently developed for comparable mass binary black holes to these Teukolsky waveforms, we improve the EOB model for the (2,2), (2,1), (3,3), and (4,4) modes. Our results can be used to quickly and accurately extract useful information about merger waves for binaries with spin, and should be useful for improving analytic models of such binaries.