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arXiv · 1207.5331

Shear viscosity of an ultrarelativistic Boltzmann gas with isotropic inelastic scattering processes

Andrej El·Francesco Lauciello·Christian Wesp·Ioannis Bouras·Zhe Xu·Carsten Greiner
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Abstract

We derive an analytic expression for the shear viscosity of an ultra-relativistic gas in presence of both elastic $2\to 2$ and inelastic $2\leftrightarrow 3$ processes with isotropic differential cross sections. The derivation is based on the entropy principle and Grad's approximation for the off-equilibrium distribution function. The obtained formula relates the shear viscosity coefficient $η$ to the total cross sections $σ_{22}$ and $σ_{23}$ of the elastic resp. inelastic processes. The values of shear viscosity extracted using the Green-Kubo formula from kinetic transport calculations are shown to be in excellent agreement with the analytic results which demonstrates the validity of the derived formula.

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Andrej El, Francesco Lauciello, Christian Wesp, Ioannis Bouras, Zhe Xu, Carsten Greiner. 2014-04-25. Shear viscosity of an ultrarelativistic Boltzmann gas with isotropic inelastic scattering processes. https://doi.org/10.1016/j.nuclphysa.2014.02.009

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