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| Measurement and Uncertainty Analysis of Absorbed Dose to Water of High-energy Photons in Medical Accelerator |
| WANG Zhi-peng1,2,WANG Kun2,JIN Sun-jun2,YANG Xiao-yuan2,FAN Yao-dong3,ZHANG Jian2 |
1. School of Mechanical Electronic and Control Engineering, Beijing Jiaotong University, Beijing 100044, China
2. National Institute of Metrology, Beijing 100029, China
3. Beijing Institute of Metrology, Beijing 100029, China |
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Abstract In view of the doubts in the use of 60Co absorbed dose to water calibration factor in the ionization chamber, the calibration factor of absorbed dose to water given by NIM was described in detail. According to the difference of correction items between calibrating ionization chamber and medical accelerator, the correction items were analyzed. The uncertainty of calibration chamber in 60Co radiation field is 0.71%, and the uncertainty of absorbed dose to water of high-energy photons in accelerator is 1.30%. Finally, the suggestions and precautions for calibrating absorbed dose to water of accelerator high-energy photons were given.
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Received: 19 September 2018
Published: 10 October 2019
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2019, Vol. 40 
