Memory effect from spinning unbound binaries

TL;DR

This paper develops a method to compute gravitational wave polarization states for spinning binaries on hyperbolic orbits, revealing a memory effect in both polarizations, unlike the non-spinning case.

Contribution

It introduces a new prescription for gravitational wave polarization states including spin effects and radiation reaction for unbound orbits, highlighting the memory effect in spinning binaries.

Findings

Memory effect present in both polarizations for spinning binaries

Comparison shows differences between spinning and non-spinning waveforms

Provides 1PN-accurate waveforms for non-spinning unbound binaries

Abstract

We present a recently developed prescription to obtain ready-to-use gravitational wave (GW) polarization states for spinning compact binaries on hyperbolic orbits. We include leading order spin-orbit interactions, invoking 1.5PN-accurate quasi-Keplerian parametrization for the radial part of the orbital dynamics. We also include radiation reaction effects on $h_+$ and $h_{\times}$ during the interaction. In the GW signals from spinning binaries there is evidence of the memory effect in both polarizations, in contrast to the non-spinning case, where only the cross polarizations exhibits non-vanishing amplitudes at infinite time. We also compute 1PN-accurate GW polarization states for non-spinning compact binaries in unbound orbits in a fully parametric way, and compare them with existing waveforms.