A beam range monitor based on scintillator and multi-pixel photon counter arrays for heavy ions therapy

作     者：Wei Wang Xiao-Xiao Yuan Xiao-Hong Cai Wei Wang;Xiao-Xiao Yuan;Xiao-Hong Cai

作者机构：Institute of Modern PhysicsChinese Academy of SciencesLanzhou 730000China University of Chinese Academy of SciencesBeijing 100049China 

出 版 物：《Nuclear Science and Techniques》 (核技术（英文）)

年 卷 期：2022年第33卷第10期

页      面：11-21页

核心收录：

学科分类：0710[理学-生物学] 0831[工学-生物医学工程（可授工学、理学、医学学位）] 082704[工学-辐射防护及环境保护] 1002[医学-临床医学] 1001[医学-基础医学(可授医学、理学学位)] 08[工学] 1010[医学-医学技术（可授医学、理学学位）] 0804[工学-仪器科学与技术] 0827[工学-核科学与技术] 100106[医学-放射医学] 0702[理学-物理学] 10[医学] 

基　　金：supported by the National Natural Science Foundation of China (Nos.11675232 and 12175286) 

主　　题：Beam range Scintillator Multi-pixel photon counter(MPPC) Depth-light curve 

摘      要：Fast beam range measurements are required to maximize the time available for patient treatment, given that the beam range requires verification with respect to quality assurance to maintain accelerator commissioning standards and ensure patient safety. A novel beam range monitor based on a plastic scintillator and multi-pixel photon counter (MPPC) arrays is therefore proposed in this paper. The monitor was constructed using 128 plastic scintillator films with a thickness of 1 mm and an active area of 50 × 50 mm^(2). A customized MPPC array read the scintillation light of each film. The advantage of dividing the active detector volume into films is that it intercepts the particle beam and enables direct differential light yield measurement in each film, in addition to depth-light curve generation without the need for image analysis A GEANT4 simulation, including scintillator quenching effects, was implemented, and the results revealed that Birks’ law exhibited a slight little influence on the position of the beam range, only changing the shape and absolute normalization of the Bragg curve, which is appropriate for the calculation of the beam range using the depth-light curve. The performance of the monitor was evaluated using a heavy-ion medical machine in Wuwei City, Gansu Province, China. The beam range measurement accuracy of the monitor was 1 mm, and the maximum difference between the measured and reference ranges was less than0.2%, thus indicating that the monitor can meet clinica carbon ion therapy requirements.