The influence of [formula omitted]-mixing processes in [formula omitted] collisions on [formula omitted] atoms’ populations in weakly ionized helium plasmas

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 ( 1 s 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 , n ′ in ranges 4 ⩽ n < n ′ ⩽ 10 , and the atom and electron temperatures, T a , T e , in domains 5000 K ⩽ T a ⩽ T e ⩽ 20 000 K . 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 ∼ 10 - 4 . Therefore, these processes have to be included in the appropriate models of such plasmas.