一种用于双GM计数管的量程控制测量方法  

Control measurement method of range switch for dual GM counter tubes

作　　者：何资星 徐丽赟 韩留军 郭凤丽 杨根 王伟 张玲玲 HE Zixing;XU Liyun;HAN Liujun;GUO Fengli;YANG Gen;WANG Wei;ZHANG Lingling(Wuxi Huapu Microelectronics Co.Ltd.,Wuxi 214000,China)

机构地区：[1]无锡华普微电子有限公司,无锡214000

出　　处：《核技术》2024年第2期76-83,共8页Nuclear Techniques

摘　　要：实现双盖格-米勒(Geiger-Müller,GM)计数管量程扩展测量的关键是双GM计数管量程切换控制技术,该技术可使探测器自动选择合适量程的GM计数管进行测量。但是由于两种不同测量量程的GM计数管存在性能差异,传统的将测量量程分成两个区域的方法会导致双GM计数管在量程交叠区域内线性拟合度较低。为了提高双GM计数管在测量量程交叠区域内的线性度,提出了一种量程控制测量方法。该方法将测量范围划分为低量程、中量程以及高量程三个区间,并且还可在三个测量量程之间进行快速自动切换,其中在中量程测量中,分别将两个GM计数管获得的数据进行加权处理。采用^(241)Am源和^(60)Co源进行双GM计数管探测器电路测试,初步测试结果表明:设计的双GM计数管探测器可实现在三个测量量程区间内快速自动切换。同时,双GM计数管在剂量率交叠区域1000~10000μGy·h^(−1)中的线性拟合度得到改进,使得在251~25130μGy·h^(−1)的测试范围内,双GM计数管的测量线性度提高至0.9991,有效地提高了双GM计数管的整体测量线性度。[Background]Effective measurement using dual Geiger-Müller(GM)counter tubes hinges on the range switch control technology.This technology facilitates the selection of the appropriate counter tube for measurement.Nonetheless,the performance disparities between the two types of GM counter tubes imply that the conventional method of bifurcating the measurement range into two sections results in reduced linearity for the overlapping measurement ranges.[Purpose]This study aims to propose a new control method for range switching to enhance the linearity of the overlapping ranges in the measurement using dual GM counter tubes.[Methods]A dual GM counter detector was consisted of a low range GM counter tube with measurement range of 0.1μSv·h^(−1)~10 mSv·h^(−1),and a high range GM counter tube with measurement range of 1 mSv·h^(−1)~100 Sv·h^(−1).The measurement range of 0.1μSv·h^(−1)~100 Sv·h^(−1)was segmented into three categories:low,medium,and high.Rapid and automatic transitions between these three ranges were facilitated by high-voltage control circuit,measurement range control circuit and dead time regulation circuit.During the medium range of 1~10 mSv·h^(−1)measurement,two range switching threshold points were set within the overlapping area,and data from the two GM counters were weighting processed respectively in the single-chip processor,hence appropriate weighting factors that maximize the linear fit of the measurement results of the dual GM counter were obtained.Finally,the ^(241)Am source and ^(60)Co ource were employed to test the dual GM counter detector circuits.[Results]Preliminary test results indicate that the proposed dual GM counter detector facilitates fast automatic transitions among the three measurement ranges,and the linear fit of the counter tube in the overlapping area from 1000μGy·h^(−1)to 10000μGy·h^(−1)is enhanced,making the linear fit of the dual GM counter reach up to 0.9991 within the measurement range of 251~25130μGy·h^(−1).[Conclusions]The overall meas

关 键 词：双GM计数管 量程切换 交叠区域 

分 类 号：TL81[核科学技术—核技术及应用]