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Appendix A: Viscosity coefficient $\xi (T)$ from LQCD {#App:C .unnumbered}
=====================================================

Following the discussion presented in [[@Cheng:2007jq]]{}, the bulk viscosity of QGP can be calculated from the lattice QCD by Eq. (13) in that paper. We assume that the decay factors for pions and kaons are vanishing above the critical temperature of the phase transition QGP-hadrons. The quark-antiquark condensates can be neglected at temperatures higher than the critical one [@TawDom]. Therefore, Eq. (22) of Ref. [[@Cheng:2007jq]]{} would be reduced to $$\label{ze}
9\,\omega_0\,\xi = T\, s\, \left(\frac{1}{c_s^2}-3\right)-4(\rho-3p) +16|\epsilon_v|$$ where $\rho$ is the energy density and $c_s^2=dp/d\rho $ is the square of the 