【作者】 张洁； 张莹； 陈秀莲； 庞蓓蓓； 白立新；

【Author】 Zhang Jie;Zhang Ying;Chen Xiulian;Pang Beibei;Bai Lixin;Key Laboratory for Neutron Physics of Chinese Academy of Engineering Physics Institute of Nuclear Physics and Chemistry;College of Physical Science and Technology of Sichuan University;

【机构】 中国工程物理研究院中子物理学重点实验室核物理与化学研究所； 四川大学物理科学与技术学院；

【摘要】 几何因子在某些放射测量系统和放射源活度的绝对刻度中发挥着重要作用。对于不能使用解析方法求解的几何因子的计算,往往可以使用蒙特卡罗方法解决。目前罕有文献报道对于圆面探测器对不共轴、不平行的圆面源几何因子的计算。该文研究的基于蒙特卡罗方法的几何因子计算程序使用C++语言编写,可用于各种尺寸的圆面探测器对圆面源各种情况下几何因子的计算。该程序使用了方差减小技巧,并与MCNP5的计算结果进行对比,具有结果准确、计算速度快、使用方便的优点。最终使用该程序成功验证了中子深度分布分析(NDP)能谱测量系统探测器位姿的准确性,并对其移动位置进行了粗略修正。更多还原

【Abstract】 Geometric factor calculations play an important role in the absolute calibration of radioactivity measurement systems and in the determination of the activity of radioactive sources. The Monte Carlo method can always calculate the geometric factors when there is no analytical algorithm available for geometric factor calculations. There are few papers have reported the calculations of geometric factors when source and detector are both disc, but are un-coaxial and un-parallel. The program studied in this paper is based on the Monte Carlo method and is written in the C++ programming language, and, it can be used to calculate the geometric factor of a disc detector for a disc source, the detector and the source can be any size at any cases. This program integrated a variance reduction method, by comparing with the results calculated using MCNP5, it is can be concluded that the program calculates geometric factors accurately, fast and conveniently. The geometric factor calculation program verified the accuracy of the pose of the detector which applied in the NDP energy spectrum measurement system; furthermore, it corrected the detector position roughly.更多还原