Hyperons in neutron stars within Eddington-inspired Born-Infeld theory of gravity

TL;DR

This paper explores how Eddington-inspired Born-Infeld gravity influences neutron star properties with hyperons, showing that certain parameter ranges yield mass-radius relations consistent with observations and can control star size and compactness.

Contribution

It introduces a study of neutron star mass-radius relations within EiBI gravity including hyperons, identifying parameter ranges compatible with observational and cosmological constraints.

Findings

NS mass and radius are compatible with observations for specific ppa values

The parameter ppa influences neutron star size and compactness

The ppa range aligns with astrophysical-cosmological constraints

Abstract

We investigate the mass-radius relation of neutron star (NS) with hyperons inside its core by using the Eddington-inspired Born-Infeld (EiBI) theory of gravity. The equation of state of the star is calculated by using the relativistic mean field model under which the standard SU(6) prescription and hyperons potential depths are used to determine the hyperon coupling constants. We found that, for $4\times 10^{6}~\rm{m^2}~\lesssim~\kappa \lesssim~6\times 10^{6}~\rm{m^2}$, the corresponding NS mass and radius predicted by the EiBI theory of gravity is compatible with observational constraints of maximum NS mass and radius. The corresponding $\kappa$ value is also compatible with the $\kappa$ range predicted by the astrophysical-cosmological constraints. We also found that the parameter $\kappa$ could control the size and the compactness of a neutron star.