基于MCPT解法器库的专用辐射探测模拟软件研发与应用北大核心CSCD

甲状腺内^(131)I放射性活度与辐射探测结果的比例关系与甲状腺几何尺寸、探测距离等因素相关,是估算甲状腺内^(131)I含量与其可能造成的辐照损伤的关键参数。基于MCPT辐射输运数值模拟算法器库开发了用于开展NaI探测器伽马辐射测量模拟的应用程序,进而建立了多组具有不同容积的甲状腺型容器和不同探测距离的物理模型,最终通过蒙特卡罗数值计算得到了不同测量状态下探测器的探测效率。在甲状腺型容器与探测器距离较远时,数值模拟给出的结果与理论计算结果一致,证明此应用程序可用于定量分析NaI的探测效率。数值模拟结果表明,小距离模型的结果受甲状腺样容器的大小和距离的显著影响,模拟给出的探测效率表为开展深入细致的实验研究奠定了基础。

Development and application of simulation code for radiation detection based on MCPT solver library

The relationship between 131I activity in the thyroid and radiation detection results is related to the thyroid geometry, detection distance and other factors, which is a key parameter for estimating the 131I content in the thyroid and its possible irradiation damage. We developed an application for gamma radiation measurement simulation of NaI detectors based on the MCPT radiation transport numerical simulation algorithm library. Then several physical models with different volumes of thyroid containers and different detection distances were established. Finally, the detection efficiency of detectors were obtained under different measurement states by Monte Carlo numerical calculations. The results of the numerical simulation are consistent with that of the theoretical calculation when the distance between the thyroid-like container and the detector is large, which proves that the application could be used to quantitatively analyze the detection efficiency of NaI detectors. It is indicated that the detection efficiency for the detector with small distances is significantly influenced by the size of the thyroid-like container and the distance. The detection efficiency table given by the simulations provides a basis for an in-depth experimental study.