Gravitational waves from spinning compact binaries in hyperbolic orbits

TL;DR

This paper develops an efficient method to compute gravitational wave signals from spinning compact binaries on hyperbolic trajectories, highlighting the influence of spins and radiation reaction effects, including the memory effect in polarization states.

Contribution

It introduces a 1.5PN accurate quasi-Keplerian parameterization for hyperbolic orbits with spins, providing ready-to-use GW polarization states and analyzing the memory effect.

Findings

Both polarization states show the memory effect for spinning binaries.

Only cross polarization exhibits the memory effect for non-spinning binaries.

Initial comparisons with existing waveforms are performed.

Abstract

Compact binaries in hyperbolic orbits are plausible gravitational wave (GW) sources for the upcoming and planned GW observatories. We develop an efficient prescription to compute post-Newtonian (PN) accurate ready-to-use GW polarization states for spinning compact binaries, influenced by the dominant order spin-orbit interactions, in hyperbolic orbits. This is achieved by invoking the 1.5PN accurate quasi-Keplerian parameterization for the radial sector of the orbital dynamics. We probe the influences of spins and gravitational radiation reaction on $h_+$ and $h_{\times}$ during the hyperbolic passage. It turns out that both polarization states exhibit the memory effect for GWs from spinning compact binaries in hyperbolic orbits. In contrast, only cross polarization state exhibits the memory effect for GWs from non-spinning compact binaries. Additionally, we compute 1PN accurate amplitude corrected GW polarization states for hyperbolic non-spinning compact binaries in a fully parametric manner and perform initial comparisons with the existing waveforms.