Perturbative Frequency Expansion for Nearly Monochromatic Binary Black Holes Detectable with LISA

TL;DR

This paper develops a perturbative frequency expansion method to analyze nearly monochromatic binary black hole signals for LISA, enabling better measurement of frequency derivatives and extraction of astrophysical parameters.

Contribution

It introduces an extended Fisher matrix approach for frequency derivative measurement and discusses methods to infer astrophysical information from these derivatives.

Findings

Frequency derivatives can be measured with improved accuracy.

Method enables extraction of orbital eccentricity and tertiary perturbations.

Supports detection and characterization of nearly monochromatic BBH signals with LISA.

Abstract

The proposed space gravitational wave (GW) detector LISA has potential to detect stellar-mass black hole binaries (BBHs). The majority of the detected BBHs are expected to emit nearly monochromatic GWs, whose frequency evolution will be efficiently described by Taylor expansions. We study the measurability of the associated time derivative coefficients of the frequencies, by extending a recent work based on a simplified Fisher matrix analysis. Additionally, we provide qualitative discussions on how to extract astrophysical information, such as orbital eccentricity and tertiary perturbation, from the observed derivative coefficients.