Anisotropic neutron stars by gravitational decoupling

TL;DR

This paper constructs anisotropic neutron star models using gravitational decoupling, applying the method to various astrophysical objects and analyzing their stability and physical acceptability.

Contribution

It introduces a gravitational decoupling approach to generate anisotropic neutron star solutions from perfect fluid models, applicable to multiple observed compact objects.

Findings

Deformed solutions meet physical acceptability conditions.

Most stable configurations have lower compactness, like SAX J1808.4-3658 and Her X-1.

Anisotropic models are consistent with observed neutron star properties.

Abstract

In this work we obtain an anisotropic neutron star solution by gravitational decoupling starting from a perfect fluid configuration which has been used to model the compact object PSR J0348+0432. Additionally, we consider the same solution to model the Binary Pulsar SAX J1808.4-3658 and X-ray Binaries Her X-1 and Cen X-3 ones. We study the acceptability conditions and obtain that the MGD--deformed solution obey the same physical requirements as its isotropic counterpart. Finally, we conclude that the most stable solutions, according to the adiabatic index and gravitational cracking criterion, are those with the smallest compactness parameters, namely SAX J1808.4-3658 and Her X-1.