Determination of the linewidth dependence on foreign-gas pressure for 3.4-μm DF spectra

Measurement of v = 1-0, P-branch 3.4-μm DF spectra is made for DF mixed with foreign gases at a temperature of 23-250C. A cw DF laser is used as a light source, and laser intensity transmitted by the gas mixture is measured in order to determine the absorption. From the measured absorption, the ratio of cross sections Q/sub AB//Q/sub AA/ is determined, where Q/sub AB/ is the cross section for collision of DF (=A) with a foreign gas (=B) and Q/sub AA/ is for DF self-collisions. Results are obtained for the single line v = 1-0, P(8) in the case of D2, He, N2, CF4, and SF6 and for the lines v = 1-0, P(5-10) in the case of HF