Possible experimental proof of nonthermal action of laser radiation on a gaseous mixture

It is shown that measurements of the absorption of probe radiation in a gaseous mixture excited by laser radiation makes it possible to determine purely experimentally (i.e., without any calculations) whether the action of laser radiation on the mixture is nonthermal. This requires a study of the absorption as a function of the intensity of the exciting radiation and of the temperature of the mixture at two different frequencies.