The absorption coefficient of SO2 under atmospheric conditions was measured at twenty DF laser lines. Weak absorption (α* ≲ 0.003 cm−1 atm−1) was found for a few wavelengths around 3.7 μm. Only the P4(6) line at 3.9843 μm (ν = 2509.86 cm−1) is strongly absorbed [α* = (0.44 ± 0.01) cm−1 atm−1]. The pressure dependence of the P4(6) cross section was measured. Self-broadening and foreign-gas broadening coefficients are between 1.5 and 5 MHz/Torr, and the distance from the P4(6) DF line to the center of the nearest SO2 line is (0.0043 ± 0.0004) cm−1.
© 1980 Optical Society of America
Original Manuscript: May 10, 1980
Published: October 15, 1980
J. Altmann and P. Pokrowsky, "Sulfur dioxide absorption at DF laser wavelengths," Appl. Opt. 19, 3449-3452 (1980)