NEW SOFT-ENERGY X-RAY ABSORPTION SPECTROSCOPY BEAM LINE

这个子项目是许多研究子项目中利用 资源由NIH/NCRR资助的中心拨款提供。子项目和 调查员(PI)可能从NIH的另一个来源获得了主要资金， 并因此可以在其他清晰的条目中表示。列出的机构是 该中心不一定是调查人员的机构。 用于2-5keV，BL4-3射程XAS测量的一个新的束线侧站于2008-2009年投入使用，并于2009年春季向一般用户开放。在这个能量范围内，X射线在空气中的路径长度非常短，因此整个光束路径被封闭在氦大气中，以便能够进行数据收集。为这条光束线开发的仪器结合了几个功能，以提高效率和易用性。这包括计算机控制的电动X射线狭缝，电动直线运动馈送，以及计算机控制的快门，以关闭数据点之间的光束(以减少X射线对样品的损害)。氧传感器和流量计被用来监测氦大气的纯度。LHe冷流用于将样品冷却到~50K，在用户模式下的宝贵经验正被用于进一步改进光束线和仪器。

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. A new beam line side station for XAS measurements in the 2-5 keV, BL4-3, range was commissioned in 2008-2009 and brought to general user access in the spring of 2009. In this energy range, x-rays have a very short path length in air and thus the entire beam path is enclosed in a helium atmosphere to enable data collection. The instrumentation developed for this beam line incorporate several features to improve efficiency and ease of use. This includes computer-controlled motorized x-ray slits, a motorized linear motion feed-through, and a computer-controlled shutter to close off the beam between data points (to reduce x-ray induced damage to samples). Oxygen sensors and flowmeters are utilized for monitoring the purity of the helium atmosphere. A LHe cryostream is used for cooling samples to ~50 K. Valuable experience in user mode is being used to further improve the beam line and instrumentation.