Advances in laser-based isotope ratio measurements: selected applications

Abstract

Advances in laser-based isotope ratio measurementsKerstel, E.; Gianfrani, L. Take-down policy If you believe that this document breaches copyright please contact us providing details, and we will remove access to the work immediately and investigate your claim.Downloaded from the University of Groningen/UMCG research database (Pure): http://www.rug.nl/research/portal. For technical reasons the number of authors shown on this cover page is limited to 10 maximum. ABSTRACT Small molecules exhibit characteristic ro-vibrational transitions in the near-and mid-infrared spectral regions, which are strongly influenced by isotopic substitution. This gift of nature has made it possible to use laser spectroscopy for the accurate analysis of the isotopic composition of gaseous samples. Nowadays, laser spectroscopy is clearly recognized as a valid alternative to isotope ratio mass spectrometry. Laserbased instruments are leaving the research laboratory stage and are being used by a growing number of isotope researchers for significant advances in their own field of research. In this review article, we discuss the current status and new frontiers of research on high-sensitivity and high-precision laser spectroscopy for isotope ratio analyses. Although many of our comments will be generally applicable to laser isotope ratio analyses in molecules of environmental importance, this paper concerns itself primarily with water and carbon dioxide, two molecules that were studied extensively in our respective laboratories. A complete coverage of the field is practically not feasible in the space constraints of this issue, and in any case doomed to fail, considering the large body of work that has appeared ever since the review by Kerstel in 2004 (Handbook of Stable Isotope Analytical Techniques, Chapt. 34, pp.

Water isotope ratio (δ2H and δ18O) measurements in atmospheric moisture using an optical feedback cavity enhanced absorption laser spectrometer

“…[14] In recent years, several laser spectroscopic methods have been proposed, developed, and optimized for isotopic investigations, especially in the infrared region [Kerstel, 2004;Kerstel and Gianfrani, 2008]. In this region, most molecular species exhibit strong vibrational-rotational absorption bands.…”

Measuring variations of δ<sup>18</sup>O and δ<sup>2</sup>H in atmospheric water vapour using two commercial laser-based spectrometers: an instrument characterisation study

“…picarro.com; Los Gatos Research, www.lgrinc.com) based on cavity ring-down, cavity enhanced and tunable diode laser absorption spectroscopy have been proposed in the last decade. Kerstel and Gianfrani (2008) gave a thorough review of recent advances in infrared isotope ratio spectroscopy and the main applications of this technology. Spectral selectivity and the sensitivity of the optical components as well as electronic noise associated with the setup limit the precision of infrared isotope ratio measurements (Paldus and Kachanov, 2005).…”

Deuterium excess in the atmospheric water vapour of a Mediterranean coastal wetland: regional vs. local signatures

“…Whereas cryogenic trapping provides grab samples generally averaging a couple of hours, laser spectrometry performs continuous high frequency (up to ∼ 1 Hz) measurements of δ v (Kerstel and Gianfrani, 2008). This technology offers new insights into processes that affect the isotopic composition of atmospheric water vapour and the number of studies based on continuous ground level isotope measurements over multiweek periods is continuously increasing, either using a tunable diode laser (TDL) (Lee et al, 2006;Wen et al, 2010Wen et al, , 2012Griffis et al, 2011;Welp et al, 2012), off-axis integrated cavity output spectroscopy (OA-ICOS) (Sturm and Knohl, 2010;Sunmonu et al, 2012;Farlin et al, 2013;SteenLarsen et al, 2013) or wavelength-scanned cavity ring-down spectroscopy (WS-CRDS) Tremoy et al, 2012;Steen-Larsen et al, 2013.…”