An infrared singularity in the damping rate for longitudinal gluons in hot QCD

A. Abada, O. Azi

Published 1998-07-21, updated 1999-01-08Version 2

We calculate $\gamma_l(0)$, the damping rate for longitudinal on-shell gluons with zero momentum in hot QCD using the hard-thermal-loop (htl) scheme. We find it to be divergent in the infrared, which means that in this scheme $\gamma_l(0)$ is different from $\gamma_t(0)$, the corresponding damping rate for transverse gluons which is known to be finite. This result suggests that the htl scheme is infrared sensitive and thus may need to be improved upon in this sector. We discuss this issue after we present our calculation.