DEVELOPMENT OF MERCURIC IODIDE ARRAYS FOR SYNCHROTRON RA

这项研究的长期目标是发展 建造大型能量色散x射线探测器阵列以供安装 并用于同步辐射(SR)和其他X射线研究 设施。每个阵列元素的能量分辨率为300 eV或 在6keV和超过50000 cps的计数速率能力下更好。 包含100多个元素的完整数组可以计算为 有效费率超过5x10‘6cps，目标成本约为 1000美元/元素。与下一代高亮度SR x相结合- 射线源，这些阵列将极大地增强 获得直接的结构、成键和组成信息， 已经被发现在解开机制方面是如此有用 蛋白质和酶在分子水平上发挥作用。这些数组可能是 以线性方式组织，如衍射探测器，或以二维方式组织 作为XANES、EXAFS或扫描荧光的荧光检测器 显微镜。预计国家能力和实力的增长 角度收集效率将使研究成为可能，在超低 稀释度或作为时间、温度或浓度的函数 否则是不可行或不可能的。之所以选择HgI2，是因为它 常温操作和易于钝化大大简化了 探测器的设计和建造。 先前的提议表明，HgI2可以通过开发5 元件探测器+FET子模块封装设计为紧密封装 创建阵列探测器系统前端。这项建议的具体目标 是完成20个工作能量色散阵列探测器系统， 100和400个元素。主要的中级发展项目包括： 在不降低其性能的情况下产生子模块的技术 性能，一种子模块安装技术，确保热接触和 坚固，电子隔离；先进的小型化处理 支持前端的电子设备；以及系统硬件和软件 整合。使用现有的商用电子设备为400 例如，元素探测器的成本将超过120万美元，并装满5个机架 错综复杂的设备，无法有效使用。建议数 电子模块将把成本降低5倍以上，体积减少 10，功耗降低5，并会集成放大器，堆积 将拒收和单通道分析功能整合到一台计算机中 受控CAMAC包。所有系统功能，包括校准， 能源调整、数据收集和故障检测将自动进行 通过创建适当的控制软件。建议的高级版本 电子功能将通过采用现有的设计来完成， 针对此特定需求简化、专业化和优化它们 应用，然后通过杂交过程使它们微型化。 完成的探测器系统将部署在国家同步加速器 支持现有NIH生物技术研究计划的实验室。

The long term objective of this research is to develop the capability to build large arrays of energy dispersive x-ray detectors for installation and use at Synchrotron Radiation (SR) and other x-ray research facilities. Each array element would have energy resolution of 300 eV or better at 6 KeV and a count rate capability exceeding 50,000 cps. Completed arrays, containing upwards of 100 elements, could count at effective rates over 5x10'6 cps and are targeted to cost about $1000/elements. Coupled to the next generation of high brightness SR x- ray sources, these arrays would lead to a greatly enhanced ability to obtain the direct structural, bonding and compositional information which has been found to be so useful in unravelling the mechanisms by which proteins and enzymes function at the molecular level. The arrays could be organized either linearly, as diffraction detectors, or 2-dimensionally as fluorescence detectors for XANES,EXAFS or scanning fluorescence microscopy. The projected increases in countrate capability and solid angle collection efficiency would make research possible at ultra-low dilutions or as a function of time, temperature, or concentration which would otherwise be unfeasible or impossible. HgI2 was chosen because its room temperature operation and ease of passivation vastly simplify detector design and construction. The previous proposal showed that HgI2 can be arrayed by developing a 5 element detector+FET submodule package designed to be closely packed to create an array detector system front end. This proposal's specific goal is to complete working energy dispersive array detector systems of 20, 100 and 400 elements. The major intermediate development include: techniques to produce the submodules without degrading their performance,a submodules mounting technique to assure thermal contact and rigidity with electronic isolation; advanced miniaturized processing electronics to support the front end; and system hardware and software integration. The use of existing commercial electronics for the 400 element detector, for example, would cost over $1.2M and fill 5 racks with a tangle of equipment too complex for effective use. The proposed electronics modules would reduce costs by a factor of over 5, volume by 10, power consumption by 5, and would integrate amplifier, pileup rejection and single channel analysis functions into a single, computer controlled CAMAC package. All system functions, including calibration, energy tuning, data collection and fault detection will then by automated by creation of appropriate control software. The proposed advanced in electronic function will be accomplished by taking existing designs, simplifying, specializing and optimizing them for this specific application, and then miniaturizing them by the hybridization process. The completed detector systems will be deployed at national synchrotron laboratories in support of existing NIH biotechnology research programs.