Significance of lower energy density region of neutron star and universalities among neutron star properties

TL;DR

This paper investigates the impact of low energy density regions and strange matter on neutron star properties, revealing universal relations among various neutron star characteristics using theoretical models.

Contribution

It introduces a comparative analysis of rotating neutron and strange star models, emphasizing the role of low energy density and crust regions, and confirms universal relations among their properties.

Findings

Universal relations among neutron star properties confirmed.

Low energy density and crust regions significantly influence star models.

Strange matter presence affects neutron star characteristics.

Abstract

We have constructed and compared models of rotating neutron stars and strange stars, within the Hartle framework. The significance of the low energy density region and crust region inside the neutron star has been studied, along with how much the existence of strange matter above the energy density 300 MeV/fm3 can affect the neutron star properties. We have confirmed several universalities among the neutron star properties such as, dimensionless moment of inertia vs dimensionless quadrupole moment, dimensionless tidal deformability vs dimensionless moment of inertia and moment of inertia parameters vs R/2M.