Extending plasma transport theory to strong coupling through the concept of an effective interaction potential

Scott Baalrud; Jerome Daligault

doi:10.1063/1.4875282

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arXiv · 1403.1882

Extending plasma transport theory to strong coupling through the concept of an effective interaction potential

Scott Baalrud·Jerome Daligault

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Abstract

A method for extending traditional plasma transport theories into the strong coupling regime is presented. Like traditional theories, this is based on a binary scattering approximation, but where physics associated with many body correlations is included through the use of an effective interaction potential. The latter is simply related to the pair-distribution function. Modeling many body effects in this manner can extend traditional plasma theory to orders of magnitude stronger coupling. Theoretical predictions are tested against molecular dynamics simulations for electron-ion temperature relaxation as well as diffusion in one component systems. Emphasis is placed on the connection with traditional plasma theory, where it is stressed that the effective potential concept has precedence through the manner in which screening is imposed. The extension to strong coupling requires accounting for correlations in addition to screening. Limitations of this approach in the presence of strong caging is also discussed.

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Scott Baalrud, Jerome Daligault. 2014-03-07. Extending plasma transport theory to strong coupling through the concept of an effective interaction potential. https://doi.org/10.1063/1.4875282

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