Design and performance evaluation of a large field-of-view dual-particle time-encoded imager based on a depth-of-interaction detector  

作　　者：Dong Zhao Xu-Wen Liang Ping-Kun Cai Wei Cheng Wen-Bao Jia Da-Qian Hei Qing Shan Yong-Sheng Ling Chao Shi 

机构地区：[1]Department of Nuclear Science and Technology,Nanjing University of Aeronautics and Astronautics,Nanjing 211106,China [2]Collaborative Innovation Center of Radiation Medicine of Jiangsu Higher Education Institutions,Suzhou 215000,China [3]School of Nuclear Science and Technology,Lanzhou University,Lanzhou 730000,China

出　　处：《Nuclear Science and Techniques》2024年第4期1-14,共14页核技术（英文）

基　　金：supported by the National Natural Science Foundation of China(Nos.11975121,12205131);the Fundamental Research Funds for the Central Universities(No.lzujbky-2021-sp58);the Postgraduate Research&Practice Innovation Program of Jiangsu Province(No.KYCX22_0354)。

摘　　要：Time-encoded imaging is useful for identifying potential special nuclear materials and other radioactive sources at a distance.In this study,a large field-of-view time-encoded imager was developed for gamma-ray and neutron source hotspot imaging based on a depth-of-interaction(DOI)detector.The imager primarily consists of a DOI detector system and a rotary dual-layer cylindrical coded mask.An EJ276 plastic scintillator coupled with two SiPMs was designed as the DOI detector to increase the field of view and improve the imager performance.The difference in signal time at both ends and the log of the signal amplitude ratio were used to calculate the interaction position resolution.The position resolution of the DOI detector was calibrated using a collimated Cs-137 source,and the full width at half maximum of the reconstruction position of the Gaussian fitting curve was approximately 4.4 cm.The DOI detector can be arbitrarily divided into several units to independently reconstruct the source distribution images.The unit length was optimized via Am-Be source-location experiments.A multidetector filtering method is proposed for image denoising.This method can effectively reduce image noise caused by poor DOI detector position resolution.The vertical field of view of the imager was(-55°,55°)when the detector was placed in the center of the coded mask.A DT neutron source at 20 m standoff could be located within 2400 s with an angular resolution of 3.5°.

关 键 词：Time-encoded imager Depth-of-interaction detector Dual-particle imaging Hotspot imaging 

分 类 号：TL81[核科学技术—核技术及应用] TP391.41[自动化与计算机技术—计算机应用技术]