Production of soft dileptons in the quark-gluon plasma

Abstract

The production rate for soft dileptons in a hot quark-gluon plasma is computed to leading order in the QCD coupling constant through a systematic resummation of perturbation theory. The partial rate from the annihilation and decay of soft quarks and antiquarks exhibits unexpected structure—sharp peaks due to Van Hove singularities. These peaks are overwhelmed by the partial rate from processes involving hard quarks and gluons. The total rate for soft dileptons is larger than the naive one-loop prediction by orders of magnitude.