Integral cross sections for electron impact excitations of argon and carbon dioxide

Practical applications require integral cross sections in a wide collision energy range from the excitation threshold to several keV. The recent developed BE-scaling method is able to meet the demands of integral cross sections for dipole-allowed transitions while the prerequisite relies on the accurate generalized oscillator strengths.

Fast electron and X-ray scattering are the conventional experimental techniques to approach the generalized oscillator strengths and the joint study by both methods provides credible cross-checks. The validated generalized oscillator strengths can then be used to extrapolate optical oscillator strength by fitting with the Lassettre formula. The fitted curve also enables the integration of generalized oscillator strengths over the whole momentum transfer region to obtain the BE-scaled integral excitation cross sections.