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arXiv · 1506.01828

Measuring the Boltzmann constant by mid-infrared laser spectroscopy of ammonia

S. Mejri·Papa Sow·O. Kozlova·C. Ayari·Sean Tokunaga·C. Chardonnet·S. Briaudeau·B. Darquié·F. Rohart·C. Daussy
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Abstract

We report on our ongoing effort to measure the Boltzmann constant, $k_B,$ using the Doppler broadening technique on ammonia. This paper presents some of the improvements made to the mid-infrared spectrometer including the use of a phase-stabilized quantum cascade laser, a lineshape analysis based on a refined physical model and an improved fitting program 2 increasing the confidence in our estimates of the relevant molecular parameters, and a first evaluation of the saturation parameter and its impact on the measurement of k B. A summary of the systematic effects contributing to the measurement is given and the optimal experimental conditions for mitigating those effects in order to reach a competitive measurement of $k_B$ at a part per million accuracy level are outlined.

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S. Mejri, Papa Sow, O. Kozlova, C. Ayari, Sean Tokunaga, C. Chardonnet, S. Briaudeau, B. Darquié, F. Rohart, C. Daussy. 2015-06-05. Measuring the Boltzmann constant by mid-infrared laser spectroscopy of ammonia. https://doi.org/10.1088/0026-1394/52/5/s314

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