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arXiv · 2004.07518

High-resolution analysis of the ${\nu_3}$ band of radiocarbon methane $^{14}CH_{4}$

Santeri Larnimaa·Lauri Halonen·Juho Karhu·Teemu Tomberg·Markus Metsälä·Guillaume Genoud·Tuomas Hieta·Steven Bell·Markku Vainio
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Abstract

We present the first high-resolution measurements and rotational analysis of the fundamental asymmetric stretching vibrational band ${\nu_3}(F_2)$ of radiocarbon methane. A spectrometer consisting of a mid-infrared continuous-wave optical parametric oscillator and a cantilever-enhanced photoacoustic detector was employed to determine the wavenumbers of 43 rovibrational lines. A spectroscopic model could reproduce all the observed transition wavenumbers within the accuracy of the experiment. Our work contributes to the development of radiocarbon methane detectors based on laser spectroscopy.

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Santeri Larnimaa, Lauri Halonen, Juho Karhu, Teemu Tomberg, Markus Metsälä, Guillaume Genoud, Tuomas Hieta, Steven Bell, Markku Vainio. 2020-04-16. High-resolution analysis of the ${\nu_3}$ band of radiocarbon methane $^{14}CH_{4}$. https://doi.org/10.1016/j.cplett.2020.137488

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