Role of the symmetry energy and the neutron-matter stiffness on the tidal deformability of a neutron star with unified equations of state

TL;DR

This paper investigates how the symmetry energy and neutron-matter stiffness influence neutron star tidal deformability using unified equations of state derived from nuclear energy-density functional theory, comparing predictions with gravitational-wave and electromagnetic observations.

Contribution

It introduces a set of unified equations of state based on nuclear energy-density functional theory to study neutron star properties, ensuring thermodynamic consistency across all regions.

Findings

Predictions align with constraints from GW170817 gravitational-wave data.

The symmetry energy significantly affects neutron star tidal deformability.

Neutron-matter stiffness impacts the star's response to tidal forces.

Abstract

The role of the symmetry energy and the neutron-matter stiffness on the tidal deformability of a cold nonaccreted neutron star is studied using a set of unified equations of state. Based on the nuclear energy-density functional theory, these equations of state provide a thermodynamically consistent treatment of all regions of the star and were calculated using functionals that were precision fitted to experimental and theoretical nuclear data. Predictions are compared to constraints inferred from the recent detection of the gravitational-wave signal GW170817 from a binary neutron-star merger and from observations of the electromagnetic counterparts.