GAUGE INVARIANT DESCRIPTION OF THE PLASMON IN HOT QCD

QCD plasma dynamics at high temperatures is examined by introducing gauge-fixing independent correlation functions of properly defined gauge invariant nonlocal currents. The linear response theory is applied to study plasma oscillations by explicitly performing one-loop calculations in the real time formalism. Our results agree with the commonly accepted expression for the plasmon frequency, whereas the damping width we find is positive and turns out to coincide with that obtained by physical gauge calculations. The role of the nonlocality of the gauge invariant colour currents in reconciling the positivity of the width with ultraviolet asymptotic freedom is stressed. © 1990.