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تسجيل مستخدم جديدViscous coefficients and thermal conductivity of a $pi K N$ gas mixture in the medium
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The temperature and density dependence of the relaxation times, thermal conductivity, shear viscosity and bulk viscosity for a hot and dense gas consisting of pions, kaons and nucleons have been evaluated in the kinetic theory approach. The in-medium cross-sections for $pipi$, $pi K$ and $pi N$ scatterings were obtained by using complete propagators for the exchanged $rho$, $sigma$, $K^*$ and $Delta$ excitations derived using thermal field theoretic techniques. Notable deviations can be observed in the temperature dependence of $eta$, $zeta$ and $lambda$ when compared with corresponding calculations using vacuum cross-sections usually employed in the literature. The value of the specific shear viscosity $eta/s$ is found to be in agreement with available estimates.
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