Trace Anomaly, Thermal Power Corrections and Dimension Two condensates in the deconfined phase

TL;DR

This paper investigates the trace anomaly in gluodynamics above the deconfinement transition, revealing a dimension two condensate's presence through lattice data and comparing various determination methods.

Contribution

It provides new lattice-based evidence for a dimension two condensate in the deconfined phase and compares different approaches to estimate its value.

Findings

Dimension two condensate manifests through inverse temperature powers.

Perturbative contributions are small and compatible with zero.

Different methods yield similar condensate values.

Abstract

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 qq free energy, yielding roughly similar numerical values. The role of glueballs near the transition is also discussed.