Influence of molecular gas impurities on the energy characteristics of sealed carbon monoxide lasers

The results are given of an investigation into the effects of oxygen, hydrogen, and carbon dioxide impurities on the energy characteristics of sealed room-temperature CO lasers. It was found that around 0.025 Torr of oxygen and carbon dioxide and around 0.04 Torr of hydrogen were sufficient to halve the output power and efficiency of a laser utilizing an Xe:CO:N₂:He = 1.25:1:3.25:12.5 gas mixture at a total pressure of about 18 Torr. Small amounts of the impurity gases led to a change in the chemical composition of the active gas mixture and, most important of all, to an increase in the concentration of the CO₂ molecules which was strikingly manifested in simultaneous lasing due to the CO and CO₂ molecular transitions. A brief discussion is given of the mechanism whereby the impurity gases influence the characteristics of sealed CO lasers.