Neutron star equation of state and tidal deformability with nuclear energy density functionals

TL;DR

This paper reviews how nuclear energy density functionals, including the KIDS model, can predict neutron star properties like mass, radius, and tidal deformability, aligning with recent gravitational wave and electromagnetic observations.

Contribution

It demonstrates that various nuclear energy density functionals are consistent with current observational constraints and discusses future experimental and observational constraints.

Findings

Many functionals satisfy observational constraints

KIDS model effectively predicts neutron star properties

Potential for future constraints from experiments and multi-messenger data

Abstract

Neutron star is the ultimate testing place for the physics of dense nuclear matter. Before the detection of gravitational waves from the merger of binary neutron stars, various nuclear equations of state have been used to estimate the macroscopic properties of neutron stars, such as masses and radii, based on the electromagnetic observations. However, recent observations on the tidal deformability of neutron star from the gravitational waves GW170817 opened a new era of multi-messenger astronomy and astrophysics, and many theoretical works have been extended to estimate the tidal deformability of neutron stars. In this article, we review our recent works on the application of nuclear energy density functionals to the properties of neutron stars including tidal deformability. We found that many nuclear energy density functionals, including new KIDS (Korea: IBS-Daegu-Sungkyunkwan) model, satisfy both constraints from current electromagnetic and gravitational wave observations. We discuss future possibilities of constraining nuclear matter equation of state from ground-based experiments and multi-messenger observations.