Acquisition of a UV laser system

这笔拨款为紫外激光系统提供了部分资金，该系统将与两台气源同位素比质谱仪一起使用，用于测量O2和SF6分析气体。该仪器将成为马里兰大学稳定同位素实验室进行地球化学研究的主要工具之一（www.geol.umd.edu/~jfarquha/stable_isotope_lab.htm）。该项目负责人James Farquhar曾在地球物理实验室和加州大学圣地亚哥分校担任博士后研究员期间使用并开发了激光氟化技术。PI和他的同事（学生和博士后）将把紫外激光应用于包括硫的四种稳定同位素和氧的三种稳定同位素在内的同位素比率的原位分析研究。这项研究的重点将是了解这些同位素系统在大气沉积、矿物-矿物和矿物-流体相互作用期间的同位素交换以及岩石记录中生物特征表征等主题中的应用。紫外激光系统将与高真空萃取线耦合，并用于与具有双入口和连续流同位素分析能力的质谱仪耦合的系统中。除了稳定同位素实验室的设施外，它还提供了比传统技术小几个数量级的样品分析能力。在样本有限的情况下，以及在科学解释需要高空间分辨率的情况下，这些能力非常重要。

EAR-0132377FarquharThis grant provides partial funding for a UV laser system that will be used in conjunction with two gas-source isotope ratio mass spectrometers for measurement of O2 and SF6 analyte gases. This instrument will be one of the primary tools for geochemistry research in the Stable Isotope laboratory at the University of Maryland (www.geol.umd.edu/~jfarquha/stable_isotope_lab.htm). The PI, James Farquhar has used and developed laser fluorination techniques in a previous position as a post doctoral fellowat the Geophysical Laboratory and UCSD. The PI and his colleagues (students and post docs) will apply the UV laser to research involving in-situ analyses of isotope ratios involving the four stable isotopes of sulfur and the three stable isotopes of oxygen. The focus of this research will be on understanding the application of these isotope systems to topics that include atmospheric deposition, isotopic exchange during mineral-mineral and mineral-fluid interactions, and the characterization of biological signatures in the rock record. The UV laser system will be coupled to a high vacuum extraction line and used in a system that is coupled to mass spectrometers capable of both dual inlet and continuous-flow isotope analyses. Its addition to the facilities in the Stable Isotope Laboratory provides the capabilities for analysis of samples several orders of magnitude smaller than by conventional techniques. These capabilities are important in situations where samples are limited and in cases where high spatial resolution is required for scientific interpretations.