(137)Cs γ辐照器光阑的优化设计  

Optimization Design of Diaphragm of the ^(137)Cs Irradiator

作　　者：成建波[1] 李德红[2] 姚泽恩[1] 黄建微[2] 金孙均[2] 

机构地区：[1]兰州大学,兰州730000 [2]中国计量科学研究院,北京100029

出　　处：《核电子学与探测技术》2015年第3期295-298,共4页Nuclear Electronics & Detection Technology

摘　　要：利用蒙特卡洛方法模拟计算了不同锥角外光阑准直孔条件下^(137)Caγ辐射场的均匀性和散射剂量,对外光阑进行了优化设计。通过实验与模拟计算验证了经光阑准直限束后辐射场的径向均匀性,在距离放射源中心1 m处得到了均匀性好于99%,直径大于10cm的均匀野。^(137)Csγ辐射场轴向剂量的模拟计算值、测量值与平方反比规律理论值对比差异均小于1%。使用光阑后辐射场的均匀性及轴向剂量分布规律达到了建立^(137)Csγ标准辐射场的需求。The Monte Carlo simulation of the flatness and scattering dose for the 137Cs radiation was performed with respect to different cone angle of the diaphragm collimator, and the diaphragm collimator was optimized. The flatness by using the diaphragm collimator was compared between the experimental results and calculations. The radiation field with flatness better than 99% and diameter greater than 10 cm is obtained at 1 m from the center of radiation source. The simulated results and measurements for the axial dose of the 137Cs radiation were compared with the inverse square theory and the discrepancies were both smaller than 1%. The flatness and axial dose distribution with the diaphragm collimator earl meet the requirements of 135Cs standard radiation field.

关 键 词：蒙特卡洛 光阑准直孔 均匀性 空气比释动能率 

分 类 号：TL84[核科学技术—核技术及应用]