Post-1-Newtonian tidal effects in the gravitational waveform from binary inspirals

TL;DR

This paper models the gravitational waveform from binary neutron star inspirals, including post-1-Newtonian tidal effects, to improve the accuracy of internal neutron star physics extraction from gravitational wave data.

Contribution

It provides a comprehensive calculation of tidal effects at post-1-Newtonian order, enhancing waveform models for neutron star inspirals.

Findings

Post-1-Newtonian corrections increase tidal signal by ~20% at 400 Hz.

The model accounts for all effects at this order in both dynamics and wave generation.

Linear quadrupole approximation used for neutron star tidal interactions.

Abstract

The gravitational wave signal from an inspiralling binary neutron star system will contain detailed information about tidal coupling in the system, and thus, about the internal physics of the neutron stars. To extract this information will require highly accurate models for the gravitational waveform. We present here a calculation of the gravitational wave signal from a binary with quadrupolar tidal interactions which includes all post-1-Newtonian-order effects in both the conservative dynamics and wave generation. We consider stars with adiabatically induced quadrupoles moving in circular orbits, and work to linear in the stars' quadrupole moments. We find that post-1-Newtonian corrections increase the tidal signal by approximately 20% at gravitational wave frequencies of 400 Hz.