Chiral phase transition and deconfinement in NF=2 QCD

A numerical analysis is made of the chiral transition of N-f = 2 QCD on the lattice. The issue is relevant to understand the mechanism of color confinement. A finite size scaling analysis of the specific heat and of various susceptibilities unambiguously indicates that the transition is first order, although very weak, and weaker as the quark mass is increased. A large volume and small masses are indeed needed to detect the increase with volume of the specific heat and bistability in time histories.