Speaker
Frank Michler
(University of Frankfurt)
Description
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.
Author
Frank Michler
(University of Frankfurt)
Co-authors
Dr
Björn Schenke
(Brookhaven National Laboratory)
Prof.
Carsten Greiner
(University of Frankfurt)
