Self-force gravitational waveforms for extreme and intermediate mass ratio inspirals. III: Spin-orbit coupling revisited

TL;DR

This paper investigates the combined impact of self-force effects and spin-orbit coupling on gravitational waveforms from extreme and intermediate mass ratio inspirals, highlighting the importance of including both for accurate parameter estimation.

Contribution

It revisits the effects of spin-orbit coupling alongside self-force effects on gravitational waveforms, providing new insights into their combined influence on waveform dephasing.

Findings

Both self-force and spin-orbit effects significantly influence waveform dephasing.

There exists a specific spin parameter where spin-orbit cancels self-force effects.

Ignoring mass-ratio independent dephasing can cause non-perturbative errors in parameter estimation.

Abstract

The first- and second-order dissipative self force and the first order conservative self force are applied together with spin-orbit coupling to the quasi-circular motion of a test mass in the spacetime of a Schwarzschild black hole, for extreme or intermediate mass ratios. The partial dephasing of the gravitational waveform (at the order that is independent of the system's mass ratio) due to the self force is compared with that of spin-orbit coupling. We find that accurate waveforms for parameter estimation need to include both effects. Specifically, we find a particular value for the spin parameter such that the spin-orbit effect cancels out the self-force effect on the waveform. Exclusion of dephasing effects that are independent of the mass ratio therefore might lead to a non-perturbative error in the estimation of the system's parameters.