Simultaneous Excitation and Ionization of Argon by Electrons to the Upper Laser States ofAr+

Abstract

Experimental cross sections for the simultaneous excitation and ionization of argon to the $4p$ configuration of ${\mathrm{Ar}}^{+}$ are presented. The data are found to be in considerable disagreement with previous work. Optical excitation functions for the important argon-ion laser lines are given, and the results are compared with the observed relative gains of the lines in a pulsed laser. The cross sections for excitation to the $4p{}_{}{}^2{}_{}{}^{}P$ states of ${\mathrm{Ar}}^{+}$ are found to have an $E^{-1\mathrm{}}$ dependence with energy in the range 250-700 eV, in disagreement with the asymptotic behavior predicted from the sudden approximation.