X-ray crystal polygon-mirror and its application for absolute calibration of angular positions

X射线晶体多角镜及其在角位置绝对标定中的应用

• 批准号: 13650059
• 负责人: ZHANG Xiaowei
• 金额: $ 1.92万
• 依托单位: High Energy Accelerator Research Organization (KEK)
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 2001
• 资助国家: 日本
• 起止时间: 2001 至 2002
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-13650059/
• 关键词: X-ray crystal polygon-mirror; angular absolute calibration; monolithic double-crystal monochromator

An x-ray crystal polygon-mirror is much compact than that of an optical polygonmirror. In practices, the x-ray crystal polygon-mirror is a small silicon cylinder with diameter of 1mm and height of 10mm. For conveniently using this small device, the crystal cylinder was scraped from a quadratic prism with a pedestal of the sijte of 10mm cube remained. Axis of the cylinder is <110> crystal direction, where the crystal polygon-mirror has 340 diffractions for x-ray with wavelength of 0.06968nm.There is a little difference on the angular position of x-ray diffractiop under the boundary condition of a flat crystal surface and a cylinder surface. But it was conformed practically that under the condition where the axis of the crystal polygonmirror is parallel to that of the rotary table within a quantity of sub-milliradilan, the peak position of x-ray diffractions from the cylinder crystal is consistent to that of the flat surface with position accuracy of sub-arc-second.340 Diffractions from the x-ray crystal polygon-mirror were detected) using an x-ray beam of synchrotron radiation with wavelength of 0.06968nm. Fallowing the calibration process, we evaluated a precise rotary table equipped with rotary encoder within accuracy of 1 arc-sec.

x射线晶体多角镜比光学多角镜紧凑得多。在实际应用中，x射线晶体多面镜是一个直径为1mm，高度为10mm的小硅圆柱体。为了方便使用这个小装置，从二次棱镜上刮下晶体圆柱体，保留了10mm立方体的底座。柱体轴线<110>晶体方向，其中晶体多边形镜对波长为0.06968nm的x射线有340次衍射。在平面晶体表面和圆柱表面的边界条件下，x射线衍射仪的角度位置略有不同。但实践证明，在晶体多面镜轴线与转盘轴线平行于亚毫安数的条件下，圆柱晶体的x射线衍射峰位置与平面一致，定位精度为亚弧秒。340用波长为0.06968nm的同步辐射x射线束检测了x射线晶体多面镜的衍射。在校准过程中，我们在1角秒的精度范围内评估了配备旋转编码器的精密转台。