Molecular-dynamics simulations to assess the Z dependence of electron heat conduction in weakly coupled plasmas

Classical molecular-dynamics simulations (CMDS), using the LAMMPS code, have been carried out on two components (electrons and ions) weakly coupled plasmas to investigate the variation of the electron heat conduction with respect to Z (plasma ionization).

Local electron heat conduction models, used in radiation-hydrodynamics codes to design ICF or HED experiments, stem from the seminal work of Spitzer-Harm (SH) [1] for weakly coupled plasmas. To date, most improvements in the literature have been focused on the coulomb logarithm to accommodate intermediate to strongly coupled plasmas. And yet, all these models are grafted with a Z-dependent factor, $\delta_T(Z)\approx 1/(1+3.5/Z)$ in [1], that has never before been subjected to the test of molecular-dynamics simulations.

Our CMDSs suggest values of $\delta_T(Z)$ slightly smaller than those described in SH [1].

[1] L. Spitzer and R. Harm, Phys. Rev., 89, 977 (1953)