In-situ evaluation for activated concrete in accelerator facility with scintillation-type gamma-ray spectrometer  

作　　者：Go Yoshida Hiroshi Matsumura Koichi Nishikawa Akihiro Toyoda Yoshiharu Miyazaki Kazuyoshi Masumoto Hajime Nakamura Taichi Miura 

机构地区：[1]High Energy Accelerator Research Organization(KEK),1-1 Oho,Tsukuba,Ibaraki 305-0801,Japan [2]The Medical and Pharmacological Research Center Foundation,Wo-32,Inoyama-machi,Hakui,Ishikawa 925-0613,Japan

出　　处：《辐射防护》2020年第6期545-549,共5页Radiation Protection

摘　　要：The assessment of activated concrete is particularly difficult during the decommissioning of an accelerator facility.Destructive analysis by core boring is the only method of investigating the activity of concrete material.To address this problem,an in-situ and nondestructive analysis method was developed to determineγ-ray-emitting nuclides and their specific activities in the concrete walls and floor by using a portable germanium semiconductor detector.In this work,we examined a substitute for Ge detector to establish a simpler and more convenient method.As candidates,we focused on some scintillation type spectrometers,and the possibility of a substitute for a Ge detector was examined by both simulation and experiment.The detection limits were roughly estimated through Monte Carlo simulation for various scintillation crystals,and it was found that 1.5-inch LaBr3,CeBr3,and SrI2 could distinguish the clearance level.It was confirmed that the 1.5-inch LaBr3 could reproduce the calibration curve of the Ge detector in the experiment.The required thickness and length of the radiation shield for suppressing the background radiation during the measurement was also determined for the convenience of an actual decommissioning work.

关 键 词：ACTIVATION ACCELERATOR CONCRETE scintillation detector PHITS code 

分 类 号：TU528[建筑科学—建筑技术科学] TL50[核科学技术—核技术及应用] TL814