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arXiv · hep-ph/0009215

Enhanced photon production from quark-gluon plasma: Finite-lifetime effect

Abstract

Photon production from a thermalized quark-gluon plasma of finite lifetime is studied directly in real time with a nonequilibrium formulation that includes off-shell (energy nonconserving) effects. To lowest order we find that production of direct photons form a quark-gluon plasma of temperature T ~ 200 MeV and lifetime t ~ 10-20 fm/c is strongly enhanced by off-shell (anti)quark bremsstrahlung q(\bar{q})->q(\bar{q})γ. The yield from this nonequilibrium finite-lifetime effect dominates over those obtained from higher order equilibrium rate calculations in the range of energy E > 2 GeV and falls off with a power law for E >> T.

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Shang-Yung Wang, Daniel Boyanovsky. 2000-12-22. Enhanced photon production from quark-gluon plasma: Finite-lifetime effect. https://doi.org/10.1103/physrevd.63.051702

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