摘要
为满足便携式核辐射污染监测系统研制需求,设计了一种基于Si PM的小体积α、β放射性活度测量装置。该装置的探测器部分以塑料闪烁体和Si PM为核心,使用该新型探测器能够保证高灵敏度的同时缩小系统体积;计数器部分以FPGA为核心,包含了去抖动、边沿检测、脉冲计数、数码管显示等单元;探测器输出的微弱电流脉冲信号依次经后级电荷灵敏放大、整形滤波、电平转换电路的处理,最终以标准TTL电平信号的形式输出给脉冲计数器,实现对放射性粒子的实时监测。测试结果表明:装置对α源的探测效率约为43.3%,对β源的探测效率约为11.5%,能够有效完成α、β放射性活度测量。
To meet the demand of portable nuclear radiation pollution monitoring system, a radioactivity measur- ing system based on SiPM was designed. Its volume is small and is used for α - and - β - particle activity measuring. Both the plastic scintillator and SiPM are the key devices of its detector, ensuring that it has high active and small volume. FPGA is the key devices of its counter, which has flutter -free, edge detection, pluse count and digital display models. The small signal output by detector was processed by CSA, shaping filter, filter level translator. Then the pluse counter can get the TTL signal to count. The detection efficiency of 241 Am - a source is about 43.3%, 90Sr- β source is about 11.5%. The test result indicates that it can realize activi- ty measurement of α - and - β - particle effectively.
出处
《核电子学与探测技术》
CAS
北大核心
2016年第3期241-244,共4页
Nuclear Electronics & Detection Technology
基金
国家自然科学基金资助项目(41474159)
国家863计划项目(2012AA061803)资助
