  We use a self-consistent chiral-hydrodynamic formalism which combines the
linear $\sigma$ model with second-order hydrodynamics in 2+1 dimensions to
compute the spectrum of thermal photons produced in Au+Au collisions at
$\sqrt{s_{NN}}=200$ GeV. The temperature-dependent shear viscosity of the
model, $\eta$, is calculated from the linearized Boltzmann equation. We compare
the results obtained in the chiral-hydrodynamic model to those obtained in the
second-order theory with a Lattice QCD equation of state and a
temperature-independent value of $\eta/s$. We find that the thermal photon
production is significantly larger in the latter model due to a slower
evolution and larger dissipative effects.
