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arXiv · 1303.1319

The influence of $(n-n')$-mixing processes in $He^{*}(n) + He(1s^2)$ collisions on $He^{*}(n)$ atoms' populations in weakly ionized helium plasmas

A. A. Mihajlov·Lj. M. Ignjatovic·V. A. Sreckovic·Z. Djuric
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Abstract

The results of semi-classical calculations of rate coefficients of $(n-n')$-mixing processes due to collisions of Rydberg atoms $He^{*}(n)$ with $He(1s^2)$ atoms are presented. It is assumed that these processes are caused by the resonant energy exchange within the electron component of $He^{*}(n)+He$ collision system. The method is realized through the numerical simulation of the $(n-n')$-mixing processes, and is applied for calculations of the corresponding rate coefficients. The calculations are performed for the principal quantum numbers $n,\mbox{} n'$ in ranges $4 \le n < n' \le 10$, and the atom and electron temperatures, $T_a, T_e$, in domains $5000K \le T_{a} \le T_{e} \le 20000K$. It is shown that the $(n-n')$-mixing processes can significantly influence the populations of Rydberg atoms in non-equilibrium weakly ionized helium plasmas with ionization degree $\sim 10^{-4}$. Therefore, these processes have to be included in the appropriate models of such plasmas.

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A. A. Mihajlov, Lj. M. Ignjatovic, V. A. Sreckovic, Z. Djuric. 2013-03-06. The influence of $(n-n')$-mixing processes in $He^{*}(n) + He(1s^2)$ collisions on $He^{*}(n)$ atoms' populations in weakly ionized helium plasmas. https://doi.org/10.1016/j.jqsrt.2007.09.005

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