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تسجيل مستخدم جديدTesting thermal conductivity models with equilibrium molecular dynamics simulations of the one component plasma
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Equilibrium molecular dynamics simulations are used to calculate the thermal conductivity of the one component plasma (OCP) via the Green-Kubo formalism over a broad range of Coulomb coupling strength, $0.1leGammale180$. These simulations address previous discrepancies between computations using equilibrium versus nonequilibrium methods. Analysis of heat flux autocorrelation functions show that very long ($6times10^5omega_p^{-1}$) time series are needed to reduce the noise level to allow $lesssim2%$ accuracy. The new simulations provide the first accurate data for $Gamma lesssim 1$. This enables a test of the traditional Landau-Spitzer theory, which is found to agree with the simulations for $Gamma lesssim 0.3$. It also enables tests of theories to address moderate and strong Coulomb coupling. Two are found to provide accurate extensions to the moderate coupling regime of $Gamma lesssim 10$, but none are accurate in the $Gamma gtrsim 10$ regime where potential energy transport and coupling between mass flow and stress dominate thermal conduction.
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