High-efficiency and high-resolution broad-range fluorescent x-ray spectrometry using a two-dimensional position-sensitive counter

使用二维位置敏感计数器的高效、高分辨率宽范围荧光 X 射线光谱测定

• 批准号: 09650072
• 负责人: MIZOGAWA Tatsumi
• 金额: $ 2.18万
• 依托单位: Nagaoka National College of Technology
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 1997
• 资助国家: 日本
• 起止时间: 1997 至 1999
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-09650072/
• 关键词: x-ray; spectrometer; two-dimensional; position-sensitive; proportional counter; flat crystal; 検出器; 位置有感; 結晶; マルチワイヤ比例計数管; 結晶分光器

Properties of a fluorescent x-ray spectrometer which consists of a flat crystal and a two-dimensional position-sensitive proportional counter based on the MBWC technique has been studied. Observed x-ray energy resolution generally shows non-linear dependence on the distance between a crystal and the PSPC and gives minimum around the distance equal to the distance between an x-ray source and the crystal. This phenomenon is interpreted as approximate focusing of reflected x-rays due to mosaic structure of the crystal. The dependence of the energy resolution on the PSPC-crystal distance has been measured for four crystals ; LiF (200), Si (111), graphite, and Ge (111). The "mosaic focusing" is observed most strongly for the graphite crystal. At a resolution minimum Fe Kα1 and Kα2 peaks are resolved, despite of the large mosaic spread 0.4°. As the PSPC-crystal distance increases or decreases apart from the resolution minimum, the resolution degrades with a gradient expected from the mosaic spread. This result fox a graphite crystal combined with the present spectrometer is specially important, because it means that the highest x-ray reflectivity of graphite among all the other crystals consists with moderately high energy-resolution in the present type of spectrometers. The other crystals also show the non-linearity to various extent.

研究了基于MBWC技术的平面晶体和二维位置灵敏正比计数管组成的X射线荧光谱仪的性能。观察到的X射线能量分辨率通常显示出对晶体和PSPC之间的距离的非线性依赖性，并且在等于X射线源和晶体之间的距离的距离附近给出最小值。这种现象被解释为由于晶体的镶嵌结构而引起的反射X射线的近似聚焦。已经测量了四种晶体：LiF（200），Si（111），石墨和Ge（111）的能量分辨率对PSPC-晶体距离的依赖性。石墨晶体的“马赛克聚焦”现象最为明显。在最小分辨率下，尽管有0.4°的大镶嵌展度，但Fe Kα1和Kα2峰仍被分辨。随着PSPC-晶体距离增大或减小，除了分辨率最小值之外，分辨率随着马赛克扩展所预期的梯度而降低。石墨晶体与现有光谱仪结合的这一结果特别重要，因为这意味着在所有其他晶体中石墨的最高X射线反射率与现有类型光谱仪中的中等高能量分辨率有关。其他晶体也表现出不同程度的非线性。