Influence of molecular oxygen addition on gain and generation characteristics of a cryogenic slab RF-discharge-pumped overtone CO laser

The influence of molecular oxygen addition to an active medium of a cryogenic slab RF-discharge-pumped overtone CO laser operating without active medium circulation on the threshold generation conditions and spectral and energy characteristics of laser radiation is calculated. Results of the modelling well agree with experimental data obtained at the initial period of laser operation and substantially differ from data obtained after reaching a stationary operation regime. The model sufficiently well describes characteristics of a single-pulse electron-beam controlled CO laser operated on gas mixtures comprising oxygen. In this model, the generation pulse profiles of a cryogenic slab CO laser operated on the fundamental band transitions of the CO molecule under pulsed-periodic RF pumping well agree with experimental data. The agreement is also observed for the parts of the RF-discharge power spent on exciting vibrational and electronic states of molecules. Reasons for distinctions between some other calculated and experimental data are analysed.