Enhanced photon production from quark-gluon plasma: Finite-lifetime effect- art. no. 051702

Photon production from a thermalized quark-gluon plasma of finite lifetime is studied directly in real time with a nonequilibrium formulation that inc ludes off-shell (energy nonconserving) effects. To lowest order we find tha t production of direct photons form a quark-gluon plasma of temperature T s imilar to 200 MeV and lifetime t similar to 10-20 fm/c is strongly enhanced by off-shell (anti)quark bremsstrahlung q((q) over bar)-->q((q) over bar)g amma. The yield from this nonequilibrium finite-lifetime effect dominates o ver those obtained from higher order equilibrium rate calculations in the r ange of energy E>2 GeV and falls off with a power law for E much greater th anT.