The Last Three Seconds: Packed Message delivered by Tides in Binary Neutron Star Mergers

TL;DR

This paper introduces the concept of a tidal form factor to better understand dynamical tides in neutron star mergers, providing a model that incorporates higher-order effects into gravitational waveform analysis.

Contribution

It proposes a new tidal form factor that captures dynamical tides and models its dependence on key parameters in a closed-form expression.

Findings

The tidal form factor effectively includes dynamical tide contributions.

Dependence of the form factor on deformability, spins, and inclination angles is modeled.

Provides a closed-form expression for the tidal form factor.

Abstract

It is known that the leading-order tidal effects in gravitational waveforms can be quantified by tidal deformability, while higher order terms, e.g., harmonic overtones of Love number and dynamical tides, have not been well-investigated yet. The concept of a ``form factor'', which is different from while resembles the effective tidal deformability, for the tidal interactions between neutron stars in coalescing binaries is illustrated here. The form factor effectively incorporates the contribution of dynamical tides. The dependence of tidal form factor on tidal deformability, spins, and inclination angles is modeled and expressed in a closed form.