On the appearance of hyperons in neutron stars

TL;DR

This paper investigates the conditions under which hyperons appear in neutron stars using a modern hyperon-nucleon potential within a Hartree-Fock framework, revealing that hyperons are always present and significantly impact neutron star properties.

Contribution

It introduces a new hyperon-nucleon potential derived via renormalization group methods and estimates hyperon appearance densities in neutron stars.

Findings

Hyperons are always present in neutron stars across various potentials.

Hyperon presence affects neutron star mass and radius.

Hyperons appear at specific densities estimated by the model.

Abstract

By employing a recently constructed hyperon-nucleon potential the equation of state of \beta-equilibrated and charge neutral nucleonic matter is calculated. The hyperon-nucleon potential is a low-momentum potential which is obtained within a renormalization group framework. Based on the Hartree-Fock approximation at zero temperature the densities at which hyperons appear in neutron stars are estimated. For several different bare hyperon-nucleon potentials and a wide range of nuclear matter parameters it is found that hyperons in neutron stars are always present. These findings have profound consequences for the mass and radius of neutron stars.