Laser Assisted Isotope Ratio Analysis of Atmospheric Carbon Dioxide

这项探索性研究小额资助（SGER）项目旨在开发一种分析稳定碳同位素比率和空气中二氧化碳浓度的新能力。待开发的方法是激光辅助同位素比值分析（LARA）。该技术利用固定波长的同位素激光器的特异性和光电效应的灵敏度。在这项研究中进行的研究包括优化电子、激光系统和射频放电条件，以最大限度地提高信噪比和长期稳定性。系统将在各种温度、流量和湿度条件下使用标准空气进行测试，以研究这些参数对系统精度和准确度的影响。实验将在环境空气中进行，并将使用现有空气采样网络提供的烧瓶空气样本与标准同位素比质谱法进行相互比较。LARA技术有潜力成为一种低成本、可用于固定和移动平台的现场部署研究仪器。

This Small Grant for Exploratory Research (SGER) project is an effort to develop a new capability for the analysis of stable carbon isotope ratios and carbon dioxide concentration in air. The method to be developed is laser-assisted isotope ratio anaysis (LARA). The technique utilizes fixed wavelength isotopic lasers for specificity and the optogalvanic effect for sensitivity. The research to be carried out in this study involves optimizing electronics, laser systems, and radio frequency discharge conditions to maximize signal to noise ratios and long-term stability. The system will be tested under a variety of temperature, flow and humidity conditions using standard air in order to study the effect of these parameters on system precision and accuracy. Experiments will be carried out with ambient air and intercomparisons with standard isotope ratio mass spectrometry will be done using flask air samples provide by existing air sampling networks. The LARA technique has the potential to be a low-cost, field deployable research instrument for use on fixed and mobile platforms.