Conditions for forming different surface plasma states during quasi-cw action of CO2 laser radiation

An experimental investigation was made of the conditions for the appearance of an erosion jet, an optical discharge in target vapor, and a discharge in the surrounding gas close to material surfaces irradiated with a quasi-cw CO₂ laser (t_p = 1 msec). A study was made of a large number of materials at various pressures of different gases and for different focal spots. The data obtained were systematized and their analysis enabled a number of important laws governing the formation of a surface plasma during quasi-cw interaction to be established.