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arXiv · 1209.2470

Production of thermal photons in a simple chiral-hydrodynamic model

J. Peralta-Ramos·M. S. Nakwacki
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Abstract

We use a self-consistent chiral-hydrodynamic formalism which combines the linear $σ$ 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, $η$, 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 $η/s$. We find that the thermal photon production is significantly larger in the latter model due to a slower evolution and larger dissipative effects.

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J. Peralta-Ramos, M. S. Nakwacki. 2012-09-12. Production of thermal photons in a simple chiral-hydrodynamic model. https://doi.org/10.1142/s2010194512008483

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