Color–flavor unlocking and phase diagram with self-consistently determined strange-quark masses Original Research Article

The phase diagram of strongly interacting matter at nonzero temperature and baryon chemical potential is calculated within a three-flavor NJL-type quark model with realistic quark masses. The model exhibits spontaneous chiral symmetry breaking as well as diquark condensation in the two-flavor color-superconducting phase and in the color–flavor-locked phase. We investigate the color–flavor-unlocking phase transition, taking into account self-consistently calculated effective quark masses. We find that it is mainly triggered by a first-order phase transition with respect to the strange-quark mass. It takes place at much higher values of the chemical potential than the transition to the hadronic phase such that we find a relatively large region in the phase diagram where the two-flavor color-superconductor seems to be the most favored state.