Universal behavior of compact star based upon gravitational binding energy

TL;DR

This paper reveals universal relations between gravitational binding energy and other stellar parameters like moment of inertia and tidal deformability, applicable to both neutron and quark stars, aiding in their characterization.

Contribution

It establishes new universal relations linking gravitational binding energy with moment of inertia and tidal deformability for neutron and quark stars.

Findings

Universal relation between GBE and moment of inertia.

Empirical relation between GBE and tidal deformability.

Potential to distinguish star types via observable parameters.

Abstract

Similar to the compactness parameter ($\beta=M/R$), the gravitational binding energy (GBE) is also a characteristic parameter which can reflect the internal structure of a neutron star and thus can be used to expressing the universal relations. Scaling by the stellar mass, this investigation demonstrates a perfect universal relation between the GBE and the moment of inertia, where both of the normal neutron stars and the quark stars satisfy the same universal relation. Moreover, a fine empirical relation between the GBE and the tidal deformability is proposed, where the difference of the relations can be used to distinguish wether a pulsar is a normal neutron star or a quark star if the stellar mass and the tidal deformability can be observed or estimated rather accurately. These universal relations provide a potential way to estimate the GBE if the stellar mass and the moment of inertia/the tidal deformability are precisely measured.