Speaker
Dr
Olaf Kaczmarek
(University of Bielefeld)
Description
We estimate the photon production rate from an SU(3) plasma at
temperatures of about $1.1~T_c$ and $1.3~T_c$. Lattice results for the
vector current correlator at spatial momenta $k\sim (2-6)T$ are
extrapolated to the continuum limit and analyzed with the help of a
polynomial interpolation for the corresponding spectral function,
which vanishes at zero frequency and matches to high-precision
perturbative results at large invariant masses. For small invariant
masses the interpolation is compared with the NLO weak-coupling
result, hydrodynamics, and a holographic model. At vanishing invariant
mass we extract the photon rate which for $k \sim 3T$ is found to be
close to the NLO weak-coupling prediction. For $k \sim 2T$
uncertainties remain large but the photon rate is likely to fall below
the NLO prediction, in accordance with the onset of a strongly
interacting behaviour characteristic of the hydrodynamic regime.
Primary author
Dr
Olaf Kaczmarek
(University of Bielefeld)