CeBr₃探测器γ辐射性能的GEANT4模拟

GEANT4 Simulation of Gamma Radiation Performance of CeBr₃ Detector

摘要: 砂岩型铀矿资源定量分析是我国研究的主攻方向，现有“直接铀定量”技术受探测晶体限制，不能很好的提取^234mPa特征峰。CeBr₃晶体作为一种高性能无机闪烁体材料，在核测井、环境监测、核医学等领域得到了广泛应用。本文使用Geant4建立CeBr₃探测器的探测模型，对影响探测器探测性质的相关因素进行研究。结果表明：在相同截面积条件下，相较于长方形截面，正方形和圆形截面的CeBr₃闪烁体表现出更高的探测效率，其中圆形截面的探测效率最优，同时伴有最大能量沉积。此外，随着入射能量的增加，CeBr₃闪烁体的探测效率呈现出下降趋势。当其他条件一致时，选用不同的反射层材料，对探测效率的并无明显影响。通过探测器探测性质的影响因素分析，对基于CeBr₃探测器研究和设计具有一定的参考价值和指导意义。

Abstract: Quantitative analysis of sandstone uranium resources is the main research direction in China. The existing technology for “direct uranium quantification” is limited by the detection crystal, which cannot extract the characteristic peaks of ^234mPa.CeBr₃ crystal, a high performance inorganic scintillator material, has been widely used in nuclear well logging, environmental monitoring and nuclear medicine. This paper investigates the factors affecting the detection characteristics of the CeBr₃ detector by establishing its detection model using Geant4. The results show that CeBr₃ scintillators with square and circular cross sections have higher detection efficiencies than those with rectangular cross sections, with the circular cross-section having the best detection efficiency and maximum energy deposition. Furthermore, the detection efficiency of CeBr₃ scintillators decreases as the incident energy increases. Other things being equal, the choice of different reflective layer materials has no significant effect on detection efficiency. The analysis of the factors influencing the detector properties provides valuable guidance for the research and design of CeBr₃- based detectors.