Using gravitational-wave data to constrain dynamical tides in neutron star binaries

TL;DR

This paper investigates how various dynamical tidal effects in neutron star binaries influence gravitational-wave signals, aiming to identify observable features and constrain neutron star physics through data analysis.

Contribution

It systematically analyzes multiple dynamical tide mechanisms and assesses their potential impact on gravitational-wave observations, providing a framework to constrain neutron star models.

Findings

Resonant oscillation modes can significantly affect gravitational-wave signals.

Nonlinear instabilities like elliptical and p-g can contribute additional energy loss.

Observational data can be used to constrain the physics of neutron star interiors.

Abstract

We discuss the role of dynamical tidal effects for inspiralling neutron star binaries, focussing on features that may be considered "unmodelled" in gravitational-wave searches. In order to cover the range of possibilities, we consider i) individual oscillation modes becoming resonant with the tide, ii) the elliptical instability, where a pair of inertial modes exhibit a nonlinear resonance with the tide, and iii) the non-resonant p-g instability which may arise as high order p- and g-modes in the star couple nonlinearly to the tide. In each case, we estimate the amount of additional energy loss that needs to be associated with the dynamical tide in order for the effect to impact on an observed gravitational-wave signal. We explore to what extent the involved neutron star physics may be considered known and how one may be able to use observational data to constrain theory.