Trace anomaly, thermal power corrections, and dimension two condensates in the deconfined phase

The trace anomaly of gluodynamics on the lattice shows clear fingerprints of a dimension two condensate above the phase transition. The condensate manifests itself through even powers of the inverse temperature while the total perturbative contribution corresponds to a mild temperature dependence and turns out to be compatible with zero within errors. We try several resummation methods based on a renormalization group improvement. The trace anomaly data are analyzed and compared with other determinations of the dimension two condensate based on the Polyakov loop and the heavy q (q) over bar free energy, yielding roughly similar numerical values. The role of glueballs near the transition is also discussed.