Kebabian P L, Zahniser M S, Kolb C E
Appl Opt. 1996 Apr 20;35(12):1942-9. doi: 10.1364/AO.35.001942.
We report the strengths and locations of the absorption lines of CH(3)D, (13)CH(4), and (12)CH(4) in the vicinity of the helium-neon laser line at 2999.24 cm(-1). In this region we find intrinsically strong lines of the rare species overlapping, but not precisely coincident with, intrinsically weak lines of the major species. In methane of normal isotopic composition, the lines of all three species have comparable strengths. We show how absorption measurements of the He-Ne laser, with Zeeman splitting, can be used to determine variations of the concentrations of the rare species from standard concentrations at a calculated precision of 0.5%0.
我们报告了CH(3)D、(13)CH(4)和(12)CH(4)在2999.24 cm(-1)处氦氖激光线附近吸收线的强度和位置。在该区域，我们发现稀有物种的固有强线与主要物种的固有弱线重叠，但并非精确重合。在正常同位素组成的甲烷中，这三种物种的谱线强度相当。我们展示了如何利用具有塞曼分裂的氦氖激光吸收测量，以0.5%的计算精度确定稀有物种浓度相对于标准浓度的变化。
