Large Solid Angle Spectrometer for Synchrotron Microbeam

描述（由申请人提供）： 我们将开发一种新的X射线光谱仪，该光谱仪将提供高计数率，出色的能量分辨率和大立体角，以满足目前正在运行的同步加速器X射线微探针和纳米探针的苛刻性能要求，并在国家同步加速器设施中建造。这些X射线微束开辟了生物学，材料科学和化学研究的新途径，在纳米尺度上分析化学和生物结构。与实验技术的发展相适应，需要发展X射线探测器，以匹配X射线微探针束的能力。 拟议的X射线光谱仪将基于Photon Imaging的新多阴极探测器技术，专门设计为环形多元素阵列格式。由于探测器元件的新颖配置，光谱仪将覆盖大的立体角，提供改进的信号收集能力，更高的计数率能力，并且非常重要的是，它将提供大大改进的设计灵活性，因为它不需要低温冷却。在第一阶段，我们将设计一个4通道环形光谱仪;选择探测器，设计和制造低噪声读出电子学，并组装和表征光谱仪与放射性同位素源和X射线发生器。第二阶段将包括单片多元件探测器（6个或更多通道）的开发，这将消除第一阶段中使用的单元件器件周围的不希望的死区，从而进一步增加立体角。第二阶段还将包括光谱仪机械设计的改进。完整的6个（或更多）通道将配备定制前置放大器，多通道放大器和ADC。将开发软件，用于对各个通道进行计算机校准，并将信号多路转换为一个输出。该光谱仪将与阿贡国家实验室工作人员合作，在高级光子源的X射线微探针实验中得到充分表征。

DESCRIPTION (provided by applicant): We will develop a new x-ray spectrometer that will offer high count rate, excellent energy resolution, and large solid angle for the demanding performance requirements encountered in synchrotron x-ray microprobes and nanoprobes currently in operation and being built at the nation's synchrotron facilities. These x-ray microbeams have opened up new avenues of research in the biology, materials science, and chemistry in the analysis of chemical and biological structures on the nano-scale. Commensurate with the development of the experimental techniques needs to be a development of the x-ray detectors to match the capabilities of the x-ray microprobe beams. The proposed x-ray spectrometer will be based on Photon Imaging's new multi-cathode detector technology, specifically designed in an annular multi-element array format. Due to the novel configuration of the detector elements, the spectrometer will cover a large solid angle, offer improved signal collection capabilities, higher count rate capability and, very importantly, it will offer the vastly improved flexibility of design as it does not require cryogenic cooling. During the Phase I, we will design a 4-channel annular spectrometer; select the detectors, design and fabricate the low-noise readout electronics, and assemble and characterize the spectrometer with radioisotope sources and an x-ray generator. Phase II will include the development of a monolithic multi-element detector (6 or more channels), which will eliminate the undesirable dead area surrounding the single element devices utilized in Phase I, thereby further increasing the solid angle. The Phase II will also include refinement of the spectrometer mechanical design. The full 6 (or more) channels will be outfitted with custom preamplifiers, multi-channel amplifiers and ADCs. Software will be developed for the computer-based calibration of the individual channels and for multi-plexing of the signals into one output. The spectrometer will be fully characterized in an x-ray microprobe experiment at the Advanced Photon Source, in collaboration with Argonne National Laboratory staff.