Synergy between ground and space based gravitational wave detectors for estimation of binary coalescence parameters

TL;DR

This paper explores how combining ground and space-based gravitational wave detectors enhances the accuracy of binary coalescence parameter estimation and tests deviations from general relativity, highlighting a synergy effect.

Contribution

It demonstrates the benefits of joint ground-space detector data in improving parameter estimates and constraining alternative gravity theories, identifying optimal sensitivity ranges.

Findings

Combined detectors improve parameter estimation accuracy.

Synergy effect peaks at specific sensitivity ranges.

Enhanced constraints on deviations from general relativity.

Abstract

We study the advantage of the co-existence of future ground and space based gravitational wave detectors, in estimating the parameters of a binary coalescence. Using the post-Newtonian waveform for the inspiral of non-spinning neutron star-black hole pairs in circular orbits, we study how the estimates for chirp mass, symmetric mass ratio, and time and phase at coalescence are improved by combining the data from different space-ground detector pairs. Since the gravitational waves produced by binary coalescence also provide a suitable domain where we can study strong field gravity, we also study the deviations from general relativity using the parameterized post-Einsteinian framework. As an example, focusing on the Einstein telescope and DECIGO pair, we demonstrate that there exists a sweet spot range of sensitivity in the pre-DECIGO phase where the best enhancement due to the synergy effect can be obtained for the estimates of the post-Newtonian waveform parameters as well as the modification parameters to general relativity.