The ¹²CO₂ band at 1.6 µm is used for carbon dioxide monitoring in the Earth atmosphere. The targeted accuracy of these measurements motivates important efforts to improve the quality of the spectroscopic parameters in atmospheric conditions. In the present work, the line shapes of the R(6), R(12), R(16), R(18) and R(20) transitions of the 30013-00001 band of ¹²CO₂ in air are studied with a cavity ring down spectrometer (CRDS). For each transition, high signal-to-noise ratio spectra (between 2000 and 20000) are recorded at different temperatures (250, 274, 285, 295 and 320 K) and total pressures (50, 100, 250, 500 and 750 Torr). To this end, a spectrally narrowed and stable (sub-kHz) laser source is coupled into a temperature regulated high-finesse optical cavity. The frequency scale of each spectrum is accurately determined from measurements of the frequency of the beat note between a part of the laser light and the closest tooth of a frequency comb referenced to a rubidium clock. A multi-spectrum fit procedure with quadratic speed dependent Nelkin-Ghatak profiles, including line-mixing effects, has been used to derive for each transition, the different spectroscopic parameters and their temperature dependence. Results are discussed in comparison with previous experimental data, HITRAN2020 database and values obtained from requantized classical molecular dynamics simulations (rCMDS).

1.6 µm的¹² CO ₂波段用于监测地球大气中的二氧化碳。这些测量的目标精度促使人们努力提高大气条件下光谱参数的质量。^{在目前的工作中， 12} CO ₂的 30013-00001 波段的 R(6)、R(12)、R(16)、R(18) 和 R(20) 跃迁的线形用腔衰荡光谱仪（CRDS）研究空气中的。对于每个跃迁，在不同温度（250、274、285、295 和 320 K）和总压力（50、100、250、500 和 750 Torr）下记录高信噪比光谱（2000 和 20000 之间） . 为此，将光谱变窄且稳定（亚 kHz）的激光源耦合到温度调节的高精密度光学腔中。每个频谱的频率标度是通过测量激光的一部分与参考铷时钟的频率梳的最近齿之间的拍音频率来准确确定的。具有二次速度依赖的 Nelkin-Ghatak 轮廓的多谱拟合程序，包括线混合效应，已用于推导每个转换，不同的光谱参数及其温度依赖性。将结果与之前的实验数据、HITRAN2020 数据库和从重新量化的经典分子动力学模拟 (rCMDS) 获得的值进行了比较。