Neutron star matter with strange interactions in a relativistic quark model

TL;DR

This paper investigates how strange interactions influence neutron star matter using a relativistic quark model, revealing that strange meson-hyperon couplings lead to a stiffer equation of state and specific neutron star radii.

Contribution

It introduces a relativistic quark model with phenomenological potentials to study strange interactions and determines the impact on neutron star properties.

Findings

SU(3) couplings yield a potential depth of about -5 MeV for Lambda hyperons.

The equation of state becomes stiffer with SU(3) symmetry.

Predicted neutron star radii range from 12.7 to 13.1 km.

Abstract

The effect of strange interactions in neutron star matter and the role of the strange meson-hyperon couplings are studied in a relativistic quark model where the confining interaction for quarks inside a baryon is represented by a phenomenological average potential in an equally mixed scalar-vector harmonic form. The hadron-hadron interaction in nuclear matter is then realized by introducing additional quark couplings to $\sigma$, $\omega$, $\rho$, $\sigma^*$ and $\phi$ mesons through mean-field approximations. The meson-baryon couplings are fixed through the SU(6) spin-flavor symmetry and the SU(3) flavor symmetry to determine the hadronic equation of state (EoS). We find that the SU(3) coupling set gives the potential depth between $\Lambda$s around $-5$ MeV and favours a stiffer EoS.The radius for the canonical neutron star lies within a range of $12.7$ to $13.1$ km.