Electrical conductivity of noble gases at high pressures

Theoretical results for the electrical conductivity of noble gas plasmas are presented in comparison with experiment. The composition is determined within a partially ionized plasma model. The conductivity is then calculated using linear response theory, in which the relevant scattering mechanisms of electrons from ions, electrons, and neutral species are taken into account. In particular, the Ramsauer-Townsend effect in electron-neutral scattering is discussed and the importance of a correct description of the Coulomb logarithm in electron scattering by charged particles is shown. A detailed comparison with recent experiments on argon and xenon plasmas is given and results for helium and neon are also revisited. Excellent agreement between theory and experiment is observed, showing considerable improvement upon previous calculations.

Figure 1

Momentum transfer cross sections in dependence of energy for ei scattering (a) and ee scattering (b). Shown are results of the T-matrix (27) and the Born approximation (23), using a Debye screened potential.

Figure 2

(Color online) Experimental measurements of the ea momentum transfer cross sections as a function of energy for argon [42, 46, 47, 48] (a) and xenon [51, 52, 53] (b). Note that Hayashi data is a fit to all available data up until 1983.

Figure 3

(Color online) Conductivity of argon (a) and xenon (b) as a function of the temperature $T$, for plasma parameters see Table . ∎: experimental results [6] shown with 30% error bars. LRT calculated according to Eq. (10) using five moments, ei and ee collisions are treated using a T-matrix approach (27), ea interactions treated using experimental data ●, and a polarization potential (28) [14] ▴, respectively. Composition is obtained using COMPTRA04.

Figure 4

Conductivity of helium, neon, argon, and xenon as a function of the mass density $\rho$: Experimental data from shock compressed plasma experiments. Results of LRT calculated using a five moment approximation, a T-matrix approach for ei and ee cross sections, and experimental results for ea cross sections. Composition is obtained using COMPTRA04.