Deconfinement at finite chemical potential

In a confining, renormalisable, Dyson-Schwinger equation model of two-flavour QCD we explore the chemical-potential dependence of the dressed-quark propagator, which provides a means of determining the behaviour of the chiral and deconfinement order parameters, and low-energy pion observables. We find coincident, first order deconfinement and chiral symmetry restoration transitions at mu(c) = 375 MeV. f(pi) is insensitive to mu until mu approximate to mu(o): = 0.7 mu(c) when it begins to increase rapidly. m(pi) is weakly dependent on mu, decreasing slowly with mu and reaching a minimum 6% less than its mu = 0 value at mu = mu(o). In a two-flavour free-quark gas at mu = mu(c) the baryon number density would be approximately 3 rho(o), where rho(o) = 0.16 fm(-3); while in such a gas at mu(o) the density is rho(o). (C) 1998 Published by Elsevier Science B.V. All rights reserved.