Infrared Behaviour of The Gluon Propagator in Non-Equilibrium Situations
Abstract
The infrared behaviour of the medium modified gluon propagator in non-equilibrium situations is studied in the covariant gauge using the Schwinger-Keldysh closed-time path formalism. It is shown that the magnetic screening mass is non-zero at the one loop level whenever the initial gluon distribution function of the medium is non isotropic. For isotropic gluon distribution functions, such as those describing local equilibrium, the magnetic mass at one loop level is zero which is consistent with finite temperature field theory results. Assuming that a reasonable initial gluon distribution function can be obtained from a perturbative QCD calculation of minijets, we determine these out of equilbrium values for the initial magnetic and Debye screening masses at energy densities appropriate to RHIC and LHC. We find that typical one loop non-equilbrium magnetic screening masses are of the order of a few pion masses and are therefore of the same magnitude as the nonperturbative magnetic screening mass found at finite temperature using lattice QCD.Keywords
All Related Versions
This publication has 0 references indexed in Scilit: