A New UV Laser Oxygen Extraction System for In Situ 18O Measurement

该奖项支持一项可行性研究，该研究旨在测试一种新的系统，通过使用在紫外线(193 Nm)中发射的脉冲准分子激光，从硅酸盐岩石或矿物的厚片表面定量释放氧气。该系统将被设计为通过断键从表面释放分子，而不会对样品进行显著加热。然后，释放的分子与氟气反应释放氧气，氧气以二氧化碳气体的形式提供给质谱仪。预计该系统将改进用于稳定同位素质谱仪的现有激光来源，这些激光使用更长波长的激光，在释放含氧分子之前熔化样品，从而导致虚假的同位素分馏和方法的空间分辨率下降。

This award supports a feasibility study to test a new system for the quantitative release of oxygen from the surfaces of thick sections of silicate rocks or minerals by use of a pulsed excimer laser emitting in the ultraviolet (193 nm). The system will be designed to release molecules from the surface by breaking bonds without heating the sample significantly. The released molecules then are reacted with fluorine gas to liberate oxygen which is fed to a mass spectrometer in the form of CO2 gas. The system is expected to improve existing laser sources for stable isotope mass spectrometry which use longer wave length lasers that melt the sample before releasing oxygen-containing molecules, thereby causing spurious isotope fractionation and a degradation of the spatial resolution of the method.