Quarkyonic stars with isospin-flavor asymmetry

Abstract

We suggest an extension to isospin asymmetric matter of the quarkyonic model from McLerran and Reddy. This extension allows us to construct the $\beta$-equilibrium between quarks, nucleons and leptons. The concept of the quarkyonic matter originates from the large number of color limit for which nucleons are the correct degrees of freedom near the Fermi surface -- reflecting the confining forces -- while deep inside the Fermi sea quarks naturally appear. In isospin asymmetric matter, we suggest that this new concept can be implemented within a global isoscalar relation between the shell gaps differentiating the nucleon and the quark sectors. In addition, we impose the conservation of the isospin-flavor asymmetry in the nucleon and the quark phases. Within this model, several quarkyonic stars are constructed on top of the SLy4 model for the nucleon sector, producing a bump in the sound speed, which implies that quarkyonic stars are systematically bigger and have a larger maximum mass than the associated neutron stars. They also predict lower proton fraction at $\beta$-equilibrium, which potentially quenches fast cooling in massive compact stars.

11 pages, 9 figures

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Cited by in corpus (14)

• On the Sound Speed in Neutron Stars
• An updated nuclear-physics and multi-messenger astrophysics framework for binary neutron star mergers
• Investigating Signatures of Phase Transitions in Neutron-Star Cores
• Impact of large-mass constraints on the properties of neutron stars
• Peaks of sound velocity in two color dense QCD: quark saturation effects and semishort range correlations
• Interacting $ud$ and $uds$ quark matter at finite densities and quark stars
• Isospin asymmetry in holographic baryonic matter
• Insights on the peak in the speed of sound of ultradense matter
• Impact of massive neutron star radii on the nature of phase transitions in dense matter
• Topology and emergent symmetries in dense compact star matter
• Speed of Sound for Hadronic and Quark Phases in a Magnetic Field
• Scale symmetry and composition of compact star matter
• The sound speed and core of massive compact stars: A manifestation of hadron-quark duality
• Algebraic approach to quarkyoniclike configuration and stable diquarks in dense matter