Kucerovsky Z, Brannen E, Rumbold D G, Sarjeant W J
Appl Opt. 1973 Feb 1;12(2):226-31. doi: 10.1364/AO.12.000226.
An analytical method is described for obtaining the precise location of an absorption line and the pressure broadening coefficients due to self-broadening or foreign gas broadening from experimental measurements using a laser operating on a single line near the absorption line. These absorption line characteristics are obtained from the pressure dependence of the transmittance of the laser radiation for the gas of interest, the analysis involving a least squares fit to a family of Lorentz curves. The method includes a computer search for the region of best fit to the Lorentz profile and provides both the values of and errors in the above coefficients. The pressure broadening coefficient obtained is the same as for the more general Voigt curve. The method is applied to the absorption line of vinyl chloride near 27.972 microm and of methane near 3.392 microm and the results compared with a graphical fit to a Voigt profile. The self-broadening coefficients obtained were alpha = 0.15 x 10(-3) +/- 0.97 x 10(-4) cm(-1) Torr(-1) for vinyl chloride and alpha = 0.14 x 10(-3) +/- 0.46 x 10(-4) cm(-1) Torr(-1) for methane. The separation between the helium-neon laser line at 2947.903 cm(-1) and the methane absorption line at 2947.888 +/- 0.015 cm(-1) was found to be 0.21 x 10(-2) +/- 0.15 x 10(-2) cm(-1).
本文描述了一种分析方法，该方法通过使用在吸收线附近单谱线工作的激光器进行实验测量，来获取吸收线的精确位置以及由于自展宽或外来气体展宽导致的压力展宽系数。这些吸收线特性是从感兴趣气体的激光辐射透过率的压力依赖性中获得的，该分析涉及对一组洛伦兹曲线进行最小二乘法拟合。该方法包括计算机搜索洛伦兹轮廓的最佳拟合区域，并提供上述系数的值和误差。所获得的压力展宽系数与更一般的沃伊特曲线相同。该方法应用于氯乙烯在27.972微米附近的吸收线和甲烷在3.392微米附近的吸收线，并将结果与对沃伊特轮廓的图形拟合进行比较。获得的自展宽系数为：氯乙烯α = 0.15×10⁻³ ± 0.97×10⁻⁴ 厘米⁻¹ 托⁻¹，甲烷α = 0.14×10⁻³ ± 0.46×10⁻⁴ 厘米⁻¹ 托⁻¹。发现氦氖激光线在2947.903厘米⁻¹ 与甲烷吸收线在2947.888 ± 0.015厘米⁻¹ 之间的间隔为0.21×10⁻² ± 0.15×10⁻² 厘米⁻¹。
