The Measurement of Synchrotron Radiation Single-energy X-ray Mass-attenuation Coefficient of Air
DU Hai-yan1,2,LI Fan3,WU Jin-jie2,WANG Pei-wei2,LAI Wan-chang1,WANG Ji2,4,ZHAO Yi-dong3
1. Chengdu University of Technology, Chengdu, Sichuan 610059, China
2. Nationa Institute of Metrology, Beijing 100029, China
3. Institute of High Energy Physics, Chinese Academy of Sciences, Beijing 100049, China
4. Hebei University of Science and Technology, Shijiazhuang, Hebei 050018, China
Abstract：Tree methods to measure the mass-attenuation coefficient of air for X-rays were introduced, which induding moving distance,vacuum and EGSnrc Monte Carlo simulation. Calculation formula of air mass thickness changed in vacuum tube after evacuated was given and influence of Be window on vacuum tube to experiment was analyzed by simulation.The results of moving distance and vacuum method have a little difference and rationality of vacuum method experiment was verified.The deviation of the results between EGSnrc Monte Carlo simulation and NIST standard database is 0.01% for 6keV and 0.26% for 20 keV X-rays respectively.
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2019, Vol. 40 
