Workshop for young scientists with research interests focused on physics at FAIR

We investigate the phase structure of QCD at finite temperature and light-quark chemical potential. We improve upon earlier results for Nf=2+1 dynamical quark flavors and investigate the effects of charm quarks in an extension to Nf=2+1+1. We determine the quark condensate and the Polyakov loop potential using solutions of a coupled set of (truncated) Dyson-Schwinger-equations for the quark and gluon propagators of Landau gauge QCD. At zero chemical potential we find excellent agreement with results from lattice-QCD. With input fixed from physical observables we find only a very small influence of the charm quark onto the resulting phase diagram at finite chemical potential. We discuss the location of the emerging critical end-point and compare with expectations from lattice gauge theory.