We study the QCD phase diagram at finite temperature and baryon chemical potential by relating the behavior of the light-quark condensate to the threshold energy for the onset of perturbative QCD. These parameters are connected to the chiral symmetry restoration and the deconfinement phase transition, respectively. This relation is obtained in the framework of finite energy QCD sum rules at finite temperature and density, with input from Schwinger-Dyson methods to determine the light-quark condensate. Results indicate that both critical temperatures are basically the same within some 3% accuracy. We also obtain bounds for the position of the critical end point, ${\mu }_{Bc}\gtrsim 300\mathrm{MeV}$ and $T_c\lesssim 185\mathrm{MeV}$.

• Received 25 June 2011

DOI:https://doi.org/10.1103/PhysRevD.84.056004