On the appearance of hyperons in neutron stars

2008/11/18 by Haris Djapo, Bernd-Jochen Schaefer, Jochen Wambach · 1 voice
Physics and Astronomy · #astro-ph #hep-ph #hep-th #nucl-th

paper · pdf · doi:10.1103/physrevc.81.035803

published as Phys.Rev.C81:035803,2010 · 12 pages, 12 figures, RevTeX4; summary and conclusions are strengthened, to appear in PRC

arxiv published 2008/11/18 · arxiv created 2010/02/08 · arxiv updated 2014/11/18

Abstract

By employing a recently constructed hyperon-nucleon potential the equation of state of β-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.

Discussions

• Yes. The appearance of $\Sigma^+$ hyperons is suppressed with respect to $\Sigma^0$ and $\Sigma^-$ (and $\Lambda$ hyperons). The main factor is their positive charge, since the rest masses, and probab [stackexchange, 2 points]