A (1+1) dimensional example of Quarkyonic matter

TL;DR

This paper explores the properties of dense quark matter in a simplified (1+1) dimensional QCD model, revealing that confined excitations can persist at high densities, exemplifying Quarkyonic matter.

Contribution

It provides a detailed analysis of QCD_2 at finite density, illustrating the coexistence of confinement and high-density quark matter, and clarifies the structure using non-Abelian bosonization.

Findings

Confined excitations can persist at high density in QCD_2.

Quark matter in QCD_2 exemplifies Quarkyonic matter.

Charge-flavor-color separation elucidates the structure of dense QCD_2.

Abstract

We analyze the (1+1) dimensional QCD (QCD_2) at finite density to consider a number of qualitative issues: confinement in dense quark matter, the chiral symmetry breaking near the Fermi surface, the relation between chiral spirals and quark number density, and a possibility of the spontaneous flavor symmetry breaking. We argue that while the free energy is dominated by perturbative quarks, confined excitations at zero density can persist up to high density. So quark matter in QCD$_2$ is an example of Quarkyonic matter. The non-Abelian bosonization and associated charge-flavor-color separation are mainly used in order to clarify basic structures of QCD_2 at finite density.