A near infrared spectrometer based on the self-scanning Tm-doped fiber laser is developed. The spectrometer is applied to measurements of the water nuclear spin isomer abundances using water absorption lines in the vibrational band near 1.91 µm. The ortho/para ratio of water nuclear spin isomers is measured to be equal to 3.06 ± 0.02, which is close to the theoretical prediction of 3 at room temperature.

中文翻译：

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使用自扫描掺铥光纤激光器检测水分子的核自旋异构体

研制了一种基于自扫描掺铥光纤激光器的近红外光谱仪。该光谱仪用于使用 1.91 µm 附近振动带中的吸水线测量水核自旋异构体丰度。水核自旋异构体的邻/对比经测量等于 3.06 ± 0.02，接近室温下 3 的理论预测。