Universal Relations for Binary Neutron Star Mergers with Long-lived Remnants

TL;DR

This paper introduces a new universal relation linking pre-merger neutron star tidal deformability to the post-merger remnant's effective compactness, enabling predictions of remnant properties from gravitational wave data.

Contribution

It proposes a novel perturbative approach to relate pre-merger and post-merger neutron star parameters, extending previous numerical relativity work.

Findings

Derived a universal relation for long-lived neutron star remnants

Enabled prediction of remnant properties from pre-merger gravitational waves

Validated the relation with numerical relativity simulations

Abstract

We present a novel universal relation for binary neutron star mergers with long-lived neutron star remnants: inspired by recent work based on numerical relativity simulations, we propose a novel approach using perturbative calculations that allow us to relate the pre-merger neutron star binary tidal deformability to the effective compactness of the post-merger remnant. Our results allow for the prediction of the stellar parameters of a long-lived remnant neutron star from the study of gravitational waves emitted during the pre-merger phase.