The thermodynamics of Nf=2 QCD

The order of the chiral transition of QCD with Nf=2 has still not been established despite of its importance to understant the mechanism of confinement. We performed an in-depth numerical investigation using staggered fermions on lattices with Lt=4 and Ls=12,16,20,24,32 and quark masses amq ranging from 0.01335 to 0.307036. The expected univerality class O(4) is in clear disagreement with MC results. Indications of a first order transition are found.