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PubMed · 12608356

13CO2/12CO2 isotopic ratio measurements using a difference frequency-based sensor operating at 4.35 micrometers.

M Erdelyi·D Richter·F K Tittel
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Abstract

A portable modular gas sensor for measuring the 13C/12C isotopic ratio in CO2 with a precision of 0.8%(+/-1 sigma) was developed for volcanic gas emission studies. This sensor employed a difference frequency generation (DFG)-based spectroscopic source operating at 4.35 micrometers (approximately 2300 cm-1) in combination with a dual-chamber gas absorption cell. Direct absorption spectroscopy using this specially designed cell permitted rapid comparisons of isotopic ratios of a gas sample and a reference standard for appropriately selected CO2 absorption lines. Special attention was given to minimizing undesirable precision degrading effects, in particular temperature and pressure fluctuations.

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AtmosphereCarbon DioxideCarbon IsotopesEnvironmental MonitoringEquipment DesignEvaluation Studies as TopicGasesLasersSpectrophotometry, AtomicVolcanic EruptionsNASA Discipline Life Sciences TechnologiesNon-NASA CenterJournal ArticleResearch Support, Non-U.S. Gov'tResearch Support, U.S. Gov't, Non-P.H.S.

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M Erdelyi, D Richter, F K Tittel. 2002. 13CO2/12CO2 isotopic ratio measurements using a difference frequency-based sensor operating at 4.35 micrometers.. https://doi.org/10.1007/s00340-002-0960-2

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