PHOTOACOUSTIC MEASUREMENTS OF THE CO2 ABSORPTION COEFFICIENTS WITHIN INFRARED REGION OF CO2 LASER SPECTRUM

Absorption coefficients of the carbon dioxide (CO2) were measured at atmospheric pressure and room temperature by photoacoustic technique with a cw, line-tunable, frequency stabilized CO2 laser. The CO2 laser spectrum of our system consists in 53 lines with wavelengths ranging from 9.2 mu m to 10.8 mu m and power levels below 5 W. Measured values of the CO2 absorption coefficients are typically of 10(-3) atm(-1)cm(-1) order of magnitude, with the highest absorption coefficient of 3.01x10(-3) atm(-1)cm(-1) observed at 9P(18) laser transition. Compared with other values reported in the literature, the obtained results revealed a good agreement.