Twin Stars within the SU(3) Chiral Quark-Meson Model

TL;DR

This paper introduces stable twin star solutions in quark stars using an SU(3) Quark-Meson model, demonstrating the existence of two stable configurations with identical masses but different radii, consistent with astrophysical constraints.

Contribution

It provides new stable solutions for quark stars exhibiting twin star phenomena within the SU(3) Quark-Meson framework, incorporating chiral phase transition effects.

Findings

Identification of two stable mass-radius branches allowing twin stars.

Solutions compatible with causality and astrophysical constraints.

Consistency with observed pulsar masses.

Abstract

We present new stable solutions of the Tolman Oppenheimer Volkoff equations for quark stars using a quark matter equation of state based on the SU(3) Quark-Meson model that exhibits the onset of the chiral phase transition. These new solutions appear as two stable branches in the mass-radius relation allowing for so called twin stars, i.e. two stable quark star solutions with the same mass, but distinctly different radii. We find solutions which are compatible with causality, the stability conditions of dense matter, the astrophysical constraints of the rotation of the millisecond pulsar PSR J1748-2446ad and the 2$M_{\odot}$ pulsar mass constraint.