Quasiparticle description of lattice QCD thermodynamics - art. no. 055201

We propose a novel quasiparticle interpretation of the equation of state of deconfined QCD at finite temperature. Using appropriate thermal masses, we introduce a phenomenological parametrization of the onset of confinement i n the vicinity of the predicted phase transition. Lattice results of the en ergy density, the pressure, and the interaction measure of pure SU(3) gauge theory are excellently reproduced. We find a relationship between the ther mal energy density of the Yang-Mills vacuum and the chromomagnetic condensa te <B-2> (T). Finally, an extension to QCD with dynamical quarks is discuss ed. Good agreement with lattice data for 2, 2+1, and 3 flavor QCD is obtain ed. We also present the QCD equation of state for realistic quark masses.