L-Shell X-Ray Cross-Sections For Cl-Ar, And Ar-Ar Collisions

Measurements of total x-ray production cross sections for ${\mathrm{Ar}}^{+}$ -Ar and ${\mathrm{Cl}}^{+}$ -Ar collisions for incident energies between 200 keV and 1.5 MeV are reported. For ${\mathrm{Cl}}^{+}$ -Ar collisions, separate argon and chlorine x-ray production cross sections are extracted. The cross sections exhibit steep increases as bombarding energy is increased. Using existing measurements of Auger cross sections, values for the mean fluorescence yields as a function of bombarding energy are deduced. The increases in the x-ray production cross sections are shown to be due primarily to changes in the mean fluorescence yields. A qualitative explanation for the observations is proposed.