Abstract A crucial part of the closed fuel cycle of future fusion power plants will be isotope separation, which takes place in a cryogenic distillation refraction column, where all six hydrogen isotopologues are separated due to their different vapor pressures at a given temperature. For monitoring and process controlling, the Tritium Laboratory Karlsruhe has investigated liquid hydrogen by infrared (IR) absorption spectroscopy and presented the first successful calibration for the inactive isotopologues. Now, the new Tritium Absorption InfraRed Spectroscopy 2 (T2ApIR) experiment, which is fully tritium compatible, is under construction and aims to provide a calibration for concentration measurements of all six hydrogen isotopologues in solid, liquid, and gaseous phases via not only IR absorption but also Raman spectroscopy. One major challenge of the new experiment so far has been the design of the cryostat, which had to fulfill diverse technical and safety requirements regarding tritium compatibility, cryogenics, and overpressure and the combination of optical components for Raman and IR spectroscopy.

中文翻译：

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用于对固相、液相和气相中的所有氢同位素体进行光谱研究的低温恒温器设计

摘要 未来聚变发电厂闭式燃料循环的一个关键部分将是同位素分离，它发生在一个低温蒸馏折射塔中，所有六种氢同位素在给定温度下由于它们的蒸气压不同而被分离。为了监测和过程控制，卡尔斯鲁厄氚实验室通过红外 (IR) 吸收光谱研究了液态氢，并首次成功校准了非活性同位素体。现在，与氚完全兼容的新型氚吸收红外光谱 2 (T2ApIR) 实验正在建设中，旨在为固相、液相和气相中所有六种氢同位素体的浓度测量提供校准，而不仅仅是通过红外吸收还有拉曼光谱。