摘要
提出了MCNP模拟计算与单能体源实测修止相结合的井型γ谱仪水样效率刻度方法,基于MCNP,计算了γ射线不同能量、水样不同高度的井型NaI(Tl)γ谱仪全能峰效率值、拟合了数学模型,两者最大相对偏差小于3%,并通过点源实测验证了所提方法的可行性,建立了基于MCNP模拟计算与单点实测修正相结合的效率刻度方法。
Putting samples in the interior of a well-type γ ray spectrometer with Nal ( Tl) detectors can increase activity measurement efficiency greatly, and therefore it can cut down measuring time and reduce the mass of samples. But before using well-type γ ray spectrometer, it is necessary to acquire detection efficiencies of well-type Nal ( Tl) detector accurately as functions of gamma ray energy and the well depth. This paper presents an efficiency calibrating method of well-Type γ ray Spectrometer for water sample by combination of MCNP simulation with volume source measuring. Based on simulating a welltype Nal(Tl) detector and water samples, peak efficiencies with various gamma ray energy and various depth of water samples are calculated by MCNP4C code and meanwhile the efficiency calibration functions are also presented in this paper, which shows the biggest discrepancy between simulated and function efficiencies is less than 3%. And finally the efficiency calibrating method presented in this paper is verified by an experiment with point source.
作者
来永芳
秦婉云
高静
祁烨林
张煊
LAI Yong-fang;QIN Wan-yun;GAO Jing;QI Ye-lin;ZHANG Xuan(Institute of NBC Defense, PLA, Beijing 102205, China;Southern Theater Command, Kunming 650000, China;Research Institute of NBC Defense of Army, PLA, Beijing 100144, China)
出处
《核电子学与探测技术》
CAS
北大核心
2018年第6期861-864,共4页
Nuclear Electronics & Detection Technology
关键词
井型γ谱仪
效率刻度
MC模拟
MCNP
well-type γ ray spectrometer
efficiency calibration
Mont Carlo simulation
MCNP
