Measurements of pressure-broadening coefficients of NO and O_3 using a computerized tunable diode laser spectrometer

Abstract

Foreign-gas broadening coefficients have been measured for selected lines of ozone in the 9.2-μm region and for several R-branch lines of nitric oxide in the 5.4-μm region using a computerized tunable diode laser spectrometer. The data analysis showed the importance of fitting a Lorentzian line shape out to several times the halfwidth to obtain a correct value of the broadening coefficient. The measured broadening coefficients of nitric oxide were in good agreement with those obtained by Abels and Shaw. The results of the analysis of eleven lines in the ν₁ band and five lines in the ν₃ band of ozone show a transition-dependent broadening coefficient. The average value of the foreign-gas broadening coefficients for the measured ν₁ and ν₃ lines are 0.075 and 0.073 cm⁻¹ atm⁻¹, respectively.