Estimation of the effect of hyperonic three-body forces on the maximum mass of neutron stars

TL;DR

This paper investigates how hyperonic three-body forces influence neutron star maximum mass using a microscopic model, finding they can't fully explain the observed high masses of certain pulsars.

Contribution

It introduces a microscopic Brueckner--Hartree--Fock model with phenomenological hyperonic three-body forces to estimate their impact on neutron star masses.

Findings

Hyperonic three-body forces can increase maximum neutron star mass to 1.4-1.5 solar masses.

They are insufficient to explain neutron stars with masses around 2 solar masses.

Current hyperonic models cannot account for the heaviest observed neutron stars.

Abstract

A model based on a microscopic Brueckner--Hartree--Fock approach of hyperonic matter supplemented with additional simple phenomenological density-dependent contact terms is employed to estimate the effect of hyperonic three-body forces on the maximum mass of neutron stars. Our results show that although hyperonic three-body forces can reconcile the maximum mass of hyperonic stars with the current limit of $1.4-1.5 M_\odot$, they are unable to provide the repulsion needed to make the maximum mass compatible with the observation of massive neutron stars, such as the recent measurements of the unusually high masses of the millisecond pulsars PSR J1614-2230 ($1.97 \pm 0.04 M_\odot$) and PSR J1903+0327 ($1.667 \pm 0.021 M_\odot$).