Study of true coincidence summing effects on FEP efficiency of HPGe detectors during decay measurements at HIRFL  

作　　者：Peng-Song Zheng Fu-Rong Shi Sunil Dutt Ya-Ling Zhang Yan-Shi Zhang Wei Wang Guang-Shun Li Si-Cheng Wang Hao-Ran Yang Jin-Qi He Peng-Cong Ma Jilehu Gada Xin Ma Fan-Fei Zeng Hao Huang Chen-Sheng Gao Jian-Guo Wang 

机构地区：[1]Institute of Modern Physics,Chinese Academy of Sciences,Lanzhou 730000,China [2]School of Nuclear Science and Technology,University of Chinese Academy of Sciences,Beijing 100049,China [3]School of Nuclear Science and Technology,Lanzhou University,Lanzhou 730000,China [4]Advanced Energy Science and Technology Guangdong Laboratory,Huizhou 516007,China

出　　处：《Nuclear Science and Techniques》2025年第5期70-78,共9页核技术(英文)

基　　金：supported by the Natural Science Foundation of Gansu Province(No.22JR5RA118);the National Natural Science Foundation of China(Nos.12121005 and U1932138);the Strategic Priority Research Program of the Chinese Academy of Sciences(No.XDB34010000)。

摘　　要：The measurement of low-level radioactivity using high-purity germanium(HPGe)detectors is important in applications such as environmental background radiation,material screening,and rare decays.The dead layers,dead zones,aluminum shell thickness,and diameter of Ge crystals are the most influential factors affecting the performance of HPGe detectors;hence,precise modeling of the physical conditions of the detectors is highly desirable.In this study,the GEANT4 simulation framework with an optimized detector geometry adequately replicated the experimentally recorded spectrum.These detector simulations explored the idea of realizing a dead zone(an inactive volume)at the backend of an n-type coaxial Gecrystal.Using multigamma sources,the effect of true coincidence summing(TCS)on the full energy peak(FEP)efficiency calibration of an HPGe detector was investigated as a function of sample-to-detector distance.Good agreements between the simulated and experimental efficiencies as well as the simulated and analytically calculated summing coincidence correction coefficients were achieved.At a short distance between the source and detector,calculating the correction factors for a strong source posed challenges owing to significant deadtime and pile-up effects of the detection system.The described methodology can efficiently determine summing peak probabilities at short sample-to-detector distances.

关 键 词：Coaxial HPGe detector Detector characterization GEANT4 simulation Sum-peak Analytical approach Transfer reaction cross-section 

分 类 号：TL81[核科学技术—核技术及应用]