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arXiv · 1509.00867

A multi-term solution of the space-time Boltzmann equation for electrons in gaseous and liquid Argon

G. J. Boyle·D. G. Cocks·W. J. Tattersall·R. P. McEachran·R. D. White
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Abstract

In a recent paper [1] the scattering and transport of excess electrons in liquid argon in the hydrodynamic regime was investigated, generalizing the seminal works of Lekner and Cohen [2,3] with modern scattering theory techniques and kinetic theory. In this paper, the discussion is extended to the non-hydrodynamic regime through the development of a full multi-term space-time solution of Boltzmann's equation for electron transport in gases and liquids using a novel operator-splitting method. A Green's function formalism is considered that enables flexible adaptation to various experimental systems. The spatio-temporal evolution of electrons in liquids in the hydrodynamic regime is studied for a benchmark model Percus-Yevick liquid as well as for liquid argon. The temporal evolution of Franck-Hertz oscillations are observed for liquids, with striking differences in the spatio-temporal development of the velocity distribution function components between the uncorrelated gas and true liquid approximations in argon. Transport properties calculated from the non-hydrodynamic theory in the long time limit, and under steady-state Townsend conditions, are benchmarked against hydrodynamic transport coefficients.

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G. J. Boyle, D. G. Cocks, W. J. Tattersall, R. P. McEachran, R. D. White. 2015-08-31. A multi-term solution of the space-time Boltzmann equation for electrons in gaseous and liquid Argon. https://doi.org/10.1088/1361-6595/aa51ef

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