Systematic errors in transport calculations of shear viscosity using the Green-Kubo formalism

Abstract

The purpose of this study is to provide a reproducible framework in the use of the Green-Kubo formalism to extract transport coefficients. More specifically, in the case of shear viscosity, we investigate the limitations and technical details of fitting the auto-correlation function to a decaying exponential. This fitting procedure is found to be applicable for systems interacting both through constant and energy-dependent cross-sections, although this is only true for sufficiently dilute systems in the latter case. We find that the optimal fit technique consists in simultaneously fixing the intercept of the correlation function and use a fitting interval constrained by the relative error on the correlation function. The formalism is then applied to the full hadron gas, for which we obtain the shear viscosity to entropy ratio.

5 pages, 6 figures, to be published in Open Access Journal of Physics: Conference Series (JPCS)

References in corpus (4)

• Particle production and equilibrium properties within a new hadron transport approach for heavy-ion collisions
• Shear Viscosity of a strongly interacting system: Green-Kubo vs. Chapman-Enskog and Relaxation Time Approximation
• Shear viscosity of a hadronic gas mixture
• Determining Transport Coefficients for a Microscopic Simulation of a Hadron Gas

Cited by in corpus (3)

• Electrical conductivity and relaxation via colored noise in a hadronic gas
• Cross-conductivity: novel transport coefficients to constrain the hadronic degrees of freedom of nuclear matter
• Inclusive and effective bulk viscosities in the hadron gas