Alkire R W, Rosenbaum G, Evans G
Biosciences Division, Argonne National Laboratory, 9700 South Cass Avenue, Bldg 202, Argonne, IL 60439, USA.
J Synchrotron Radiat. 2000 Mar 1;7(Pt 2):61-8. doi: 10.1107/S090904959901568X.
The Structural Biology Center beamline, 19ID, has been designed to take full advantage of the highly intense undulator radiation and very low source emittance available at the Advanced Photon Source. In order to keep the X-ray beam focused onto the pre-sample slits, a novel position-sensitive PIN diode array has been developed. The array consists of four PIN diodes positioned upstream of a 0.5 microm-thick metal foil placed in the X-ray beam. Using conventional difference-over-the-sum techniques, two-dimensional position information is obtained from the metal foil fluorescence. Because the full X-ray beam passes through the metal foil, the true beam center-of-mass is measured. The device is compact, inexpensive to construct, operates in a vacuum and has a working range of 8 mm x 10 mm that can be expanded with design modifications. Measured position sensitivity is 1-2 microm. Although optimized for use in the 5-25 keV energy range, the upper limit can be extended by changing metals or adjusting foil thickness.
结构生物学中心光束线19ID的设计旨在充分利用先进光子源提供的高强度波荡器辐射和极低的源发射度。为了使X射线束聚焦在样品前狭缝上，已开发出一种新型的位置敏感型PIN二极管阵列。该阵列由四个PIN二极管组成，位于放置在X射线束中的0.5微米厚金属箔的上游。使用传统的和差技术，从金属箔荧光中获取二维位置信息。由于整个X射线束穿过金属箔，因此测量的是真实的束质心。该装置结构紧凑，制造成本低，在真空中运行，工作范围为8毫米×10毫米，可通过设计修改进行扩展。测量的位置灵敏度为1-2微米。虽然针对5-25keV能量范围进行了优化，但通过更换金属或调整箔厚度可以扩展上限。
