Searching for quasinormal modes from Binary Black Hole mergers

TL;DR

This paper introduces a maximum likelihood-based method for detecting and analyzing quasinormal modes in gravitational wave ringdowns from binary black hole mergers, applicable to current and future detectors.

Contribution

The paper presents a new time-domain matched-filtering technique for identifying multiple quasinormal modes and estimating their parameters in gravitational wave data.

Findings

Method successfully detects quasinormal modes in simulated noise.

Analyzes GW190521 event's ringdown with new technique.

Performs well across current and future gravitational wave detectors.

Abstract

We present a new method to search for gravitational waves from quasinormal modes in the ringdowns of the remnants of the mergers of the binary black hole systems. The method is based on maximum likelihood estimation. We derive a time-domain matched-filtering statistic that can be used to search for any number of modes in the data. The parameters of the modes can be estimated and the modes present in the data can be reconstructed. We perform Monte Carlo simulations of the method by injecting the quasinormal mode waveforms to noise. We analyze performance of the method for searches of quasinormal modes in the advanced detectors data like LIGO and Virgo, in the third generation of detectors like Einstein Telescope and Cosmic Explorer and in the space detector LISA data. We analyze ringdown of publicly available GW190521 event and we compare our results with analysis by other methods.