Confinement and chiral symmetry crossovers

Abstract

We study the QCD phase diagram, in particular we study the critical points of the two main QCD phase transitions, confinement and chiral symmetry breaking. Confinement drives chiral symmetry breaking, and, due to the finite quark mass, at small density both transitions are a crossover, while they are a first or second order phase transition in large density. We study the QCD phase diagram with a quark potential model including both confinement and chiral symmetry. This formalism, in the Coulomb gauge hamiltonian formalism of QCD, is presently the only one able to microscopically include both a quark-antiquark confining potential and a vacuum condensate of quark-antiquark pairs. This model is able to address all the excited hadrons, and chiral symmetry breaking, at the same token. Our order parameters are the Polyakov loop and the quark mass gap. The confining potential is extracted from the Lattice QCD data of the Bielefeld group. We address how the quark masses affect the critical point location in the phase diagram.

4 pages, 3 figures, contribution submitted to 45th Rencontres de Moriond, QCD and High Energy Interactions, La Thuile, March 13-20, 2010