根据X射线束光子通量、注量和空气比释动能等物理量的关系,通过空气比释动能的测量,转换确定了所需要的光子通量、注量等。依据X射线自由空气电离室原理,针对同步辐射光子束的物理条件,确定了自由空气电离室的设计方案并完成了精密加工和安装调试。电离室主要部件尺寸公差、机械性能和电性能满足计量标准的要求,为计量标准的建立提供了基础。
Abstract
According to the relationship between the photon flux, fluence and air kerma of X-ray beam, the required photon flux and fluence were determined through the measurement of air kerma. It is based on the principle of X-ray free-air ionization chamber, and aiming at the physical conditions of synchrotron radiation photon beam, the scheme and design of free-air chamber were determined and the precise processing and adjustment were completed. The dimensional tolerance, mechanical properties and electrical properties of the main parts of the ionization chamber meet the requirements of metrological standards. It provided a basis for the establishment of metrological standards. The main parts size and tolerance as well as mechanical and electrical properties, to meet the requirements of metrological standards. It provides the foundation for the establishment of metrological standard.
关键词
计量学 /
同步辐射 /
X射线 /
注量 /
绝对测量 /
自由空气电离室
Key words
metrology /
synchrotron radiation /
X-ray /
fluence /
absolute measurement /
free-air ionization chamber
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参考文献
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基金
国家自然科学基金(11375227);国家重点研发计划项目(2017YFF0205102)
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