Collaborative Research: Development of a Tender-Energy Microspectroscopy and Imaging User Facility for Earth Sciences at NSLS and NSLS-II

该项目将创建一种新的、独特的基于同步加速器的用户设施，利用专门针对较轻元素Na到Ti进行调谐的聚焦X射线束，在微米级检查地质材料。该设施是为地球科学研究的“投标”(1-8keV能量)X射线显微光谱和成像应用而设计和优化的，将补充现有的、高生产力的、运行在约4.5keV以上的“硬”X射线设施。它将扩展到较低能量的X射线荧光(XRF)和X射线吸收光谱(XAS)能力，作为元素特定的非侵入性探测器，用于研究晶体和非晶体材料中的元素分布和局部物理和电子结构和状态。此外，它还将为微束扩展X射线吸收光谱(EXAFS)提供先进的能力，以确定所选元素周围更详细的局部结构。该项目将通过在布鲁克海文国家实验室的国家同步加速器光源(NSLS)的X15B处建立和验证的宏观聚焦(~1 mm光斑尺寸)招标能量XAS光束线添加新的微观聚焦能力来实施，随后将过渡到NSLS-II正在开发的新招标能谱(TES)光束线。它的主要属性将是独特的1至8keV能量范围，用户可调的光斑大小从约50微米到1微米，高通量和稳定性优化，高质量和扩展的XAS，快速扫描的XRF和XAS映射选项，以及氦手套盒样品环境。当转移到NSLS-II时，性能将得到改善，NSLS-II是一种为高亮度应用而设计的最先进的新同步加速器。这些新能力对于提高我们对地球化学和生物地球化学过程的知识至关重要，特别是那些涉及较轻元素的过程，并将通过NSLS通用用户程序公开使用。针对的具体应用包括矿泉水界面、营养物质和污染物、碳酸盐、古气候、氧化还原过程、高压矿物学以及地球材料对健康的影响。

This project will create a new, unique synchrotron-based user facility to examine geologic materials at the micron scale with a focused X-ray beam tuned specifically for lighter elements Na through Ti. This facility is designed and optimized for "tender" (1-8 keV energy) X-ray micro-spectroscopy and imaging applications for Earth Science research, and will complement existing and highly productive "hard" X-ray facilities operating above about 4.5 keV. It will extend to lower energies the X-ray fluorescence (XRF) and X-ray absorption spectroscopy (XAS) capabilities typical of hard X-ray microprobes, as element-specific non-invasive probes of elemental distribution and local physical and electronic structures and states in crystalline and non-crystalline materials. In addition, it will offer advanced capabilities for microbeam extended X-ray absorption spectroscopy (EXAFS) for determination of more detailed local structure around the selected element. This project will be undertaken by adding new micro-focusing capabilities at an established and proven macro-focused (~1mm spot size) tender-energy XAS beamline at X15B of the National Synchrotron Light Source (NSLS) at Brookhaven National Laboratory, and will subsequently transition to the new Tender Energy Spectroscopy (TES) beamline under development at NSLS-II. Its key attributes will be the distinct 1 to 8 keV energy range, user-tunable spot size from about 50 microns to 1 micron, high flux and stability optimized for high-quality and extended XAS, options for both XRF and XAS mapping with rapid scanning, and a helium glove-box sample environment. Performance will improve when transferred to NSLS-II, a state-of-the-art new Synchrotron designed for high brightness applications. These new capabilities are critical for advancing our knowledge of geochemical and biogeochemical processes, in particular those involving lighter elements, and will be openly available for use through the NSLS General User program. Specific applications targeted include the mineral-water interface, nutrients and contaminants, carbonates, paleoclimate, redox processes, high-pressure mineralogy; and health effects of Earth materials.