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arXiv · 1706.01776

Temperature Anisotropy Relaxation of the One-Component Plasma

Scott D. Baalrud·Jerome Daligault
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Abstract

The relaxation rate of a Maxwellian velocity distribution function that has an initially anisotropic temperature $(T_\parallel \neq T_\perp)$ is an important physical process in space and laboratory plasmas. It is also a canonical example of an energy transport process that can be used to test theory. Here, this rate is evaluated using molecular dynamics simulations of the one-component plasma. Results are compared with the predictions of four kinetic theories; two treating the weakly coupled regime (1) the Landau equation, and (2) the Lenard-Balescu equation, and two that attempt to extend the theory into the strongly coupled regime (3) the effective potential theory and (4) the generalized Lenard-Balescu theory. The role of dynamic screening is studied, and is found to have a negligible influence on this transport rate. Oscillations and a delayed relaxation onset in the temperature profiles are observed at strong coupling, which are not described by the kinetic theories.

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Scott D. Baalrud, Jerome Daligault. 2017-06-06. Temperature Anisotropy Relaxation of the One-Component Plasma. https://doi.org/10.1002/ctpp.201700028

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