The Collision-Induced Absorption (CIA) fundamental band of H2 has been studied in the 3600–5500 cm−1 spectral range for temperatures ranging from 120 to 500 K for both a pure H2 gas and a H2-He mixture. We used a simulation chamber called PASSxS (Planetary Atmosphere System Simulation x Spectroscopy) developed at INAF/ISAC which contains a Multi-Pass cell interfaced with a Fourier Spectrometer, aligned to reach an optical path of 3.28 m. The H2-H2 and H2-He binary absorption coefficients (BACs) have been derived for seven temperatures in the chosen range and provided in tabular form, including the unexplored high-temperature range above 300 K. We also calculated the integral of the H2-H2 and H2-He experimental BACs in the reduced 4000–5000 cm−1 spectral range, finding a linear trend with temperature in both cases. The integrals have also been computed with larger uncertainties for the whole band, in the total 3600–5500 cm−1 spectral range including the band's wings, partially affected by the water vapor absorption. The integrals calculated over the whole and reduced spectral ranges are collected in tables. In addition, we performed measurements with a H2-He mix for different mixing ratios to explore possible deviations from the linear combination of the BACs. The experimental BACs have been shown in comparison with Abel and Borysow's ab initio models for a temperature of about 400 K, resulting in a good agreement over almost the whole spectral range, with a maximum deviation around the main peak of the band. Data and models also show a good agreement in the linear trend of the integrated BACs with temperature, apart from the H2-H2 Borysow's BACs, which follow a quadratic trend. Finally, we resolved all the interference dips, which were not taken into account by the existing theoretical models.

中文翻译：

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在 120 至 500 K 的 3600-5500 cm-1 光谱范围内对 H2-H2 和 H2-He 的碰撞诱导吸收进行的新实验测量


对于纯 H2 气体和 H2-He 混合物，已在 3600–5500 cm−1 光谱范围内研究了 H2 的碰撞诱导吸收 （CIA） 基频带，温度范围为 120 至 500 K。我们使用了由 INAF/ISAC 开发的名为 PASSxS（行星大气系统模拟 x 光谱）的模拟室，其中包含一个与傅里叶光谱仪接口的多通道单元，对齐以达到 3.28 m 的光程。H2-H2 和 H2-He 二元吸收系数 （BAC） 是针对所选范围内的 7 个温度得出的，并以表格形式提供，包括 300 K 以上未开发的高温范围。我们还计算了 H2-H2 和 H2-He 实验 BAC 在减少的 4000-5000 cm-1 光谱范围内的积分，发现在这两种情况下都呈温度线性趋势。在包括波段机翼在内的整个波段总光谱范围内的 3600–5500 cm−1 光谱范围内，部分受水蒸气吸收的影响，积分也以更大的不确定性计算得出。在整个光谱范围和缩减光谱范围内计算的积分收集在表格中。此外，我们使用 H2-He 混合物对不同的混合比例进行了测量，以探索与 BAC 线性组合的可能偏差。在大约 400 K 的温度下，实验 BAC 与 Abel 和 Borysow 的从头计算模型进行了比较，从而在几乎整个光谱范围内都具有良好的一致性，在谱带主峰附近存在最大偏差。数据和模型还显示，除了 H2-H2 Borysow 的 BAC 呈二次方趋势外，积分 BAC 与温度的线性趋势具有良好的一致性。 最后，我们解决了现有理论模型未考虑的所有干扰 Dip。