中能治疗水平X射线机发射率常数测定及MC模拟  

Determination of Emissivity Constant and MC Simulation of X-ray Machine

作　　者：刘哲[1,2] 吴金杰 曾国强[1] 赵瑞[2] 王继[2] 李云飞 LIU Zhe;WU Jin-jie;ZENG Guo-qiang;ZHAO Rui;WANG Ji;LI Yun fei(Chengdu University of Technology,Chengdu 610059,China;China Institute of Metrology,Beijing 100029,China;Hebei University of Science and Technology,Shijiazhuang 050018,China)

机构地区：[1]成都理工大学,成都610059 [2]中国计量科学研究院,北京100029 [3]河北科技大学,石家庄050018

出　　处：《核电子学与探测技术》2020年第1期10-14,共5页Nuclear Electronics & Detection Technology

基　　金：中央级公益件科研院所基本业务费,环境水平X射线空气比释动能测量方法研究(25—AKY1707)资助。

摘　　要：为研究标准CCRI辐射质下发射率常数的量值以及变化规律,建立了中能治疗水平X射线辐射场,通过自由空气电离室测量空气比释动能率并计算X射线机发射率常数量值.用MC模拟方法模拟出X射线能谱并求得粒子的平均能量.结果表明:治疗水平X射线机发射率常数随电子能量增大而增大,趋势趋于平缓并给出了标准CCRI辐射质下量值;用EGSnrc软件模拟标准CCRI辐射质下X射线能谱,附加过滤阻挡吸收低能粒子会使得能谱向右偏移,粒子数减少但平均能量变大.In order to study the magnitude and variation law of the emissivity constant under the standard CCRI radiation m ass,a medium-energy treatm ent level X-ray radiation field was established.The air kerma rate was measured by the free air ionization chamber and the X-ray machine emissivity constant value was calculated.The X-ray energy spectrum was simulated by the MC simulation method and the average energy of the particles was obtained.The results show that the emissivity constant of the therapeutic level X-ray machine increases with the increase of electron energy,the trend tends to be gentle and gives the standard CCRI radiation mass value;EGSnrc software is used to simulate the X-ray energy spectrum of standard CCRI radiation.Additional filtering and blocking absorption of low-energy particles will shift the energy spectrum to the right,and the number of particles will decrease but the average energy will increase.

关 键 词：发射率常数 CCRI辐射质 空气比释动能 能谱模拟 

分 类 号：TB98[一般工业技术—计量学]