Bonn 2010 – wissenschaftliches Programm
HK 14.3: Vortrag
Dienstag, 16. März 2010, 15:00–15:15, HG I
Finite lifetime effects on the photon production from a quark-gluon plasma — •Frank Michler1, Björn Schenke2, and Carsten Greiner1 — 1Institut für theoretische Physik, Goethe Universität Frankfurt am Main, Max von Laue Straße 1, 60438 Frankfurt am Main, Germany — 2Department of Physics, McGill University, H3A 2T8, Montreal, Quebec, Canada
Direct photons play an important role as electromagnetic probes from a quark-gluon plasma (QGP) created in heavy ion collisions. After being once produced, they leave the medium undisturbed an thus provide direct insight into the early stage of the collision. We use the real time Keldysh formalism to investigate how non-equilibrium effects such as a finite lifetime modify the resulting photon spectra. We provide an ansatz which eliminates the divergent contribution from the vacuum polarization and renders the photon spectrum UV-finite if the time evolution of the QGP is described in a suitable manner.