One-component-plasma: Going beyond Debye-Hückel
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Using field-theoretic methods, we calculate the internal energy for the One-Component Plasma (OCP). We go beyond the recent calculation by Brilliantov [N. Brilliantov, Contrib. Plasma Phys. 38, 489 (1998)] by including non-Gaussian terms. We show that, for the whole range of the plasma parameter Γ, the effect of the higher-order terms is small and that the final result is not improved relative to the Gaussian theory when compared to simulations.
PACS52.25.Kn Thermodynamics of plasmas 61.20.Gy Theory and models of liquid structure 05.20.-y Classical statistical mechanics
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