载钆液闪的(n,γ)分辨性能及中子俘获时间分布  

(n,γ) discrimination and distribution of neutron capture time measurement of gadolinium-loaded liquid scintillator

作　　者：朱传新[1] 牟云峰[1] 郑普[1] 

机构地区：[1]中国工程物理研究院核物理与化学研究所,绵阳621900

出　　处：《核技术》2014年第11期45-49,共5页Nuclear Techniques

摘　　要：本文进行了多种配比和成分载Gd量为0.5%的载钆液闪溶液研制和载钆液闪探测器制作,并进行了中子与伽玛分辨性能测试,通过实验得到在萘质量含量为7.5%时,可得到较好的中子与伽玛的分辨性能,优化了载钆液闪成分;利用252Cf裂变电离室的裂变碎片信号作为开门信号,以载钆液闪探测器的阳极信号作为关门信号,通过符合测量的方法得到了252Cf裂变中子在载Gd量为0.5%的φ13 cm×30 cm载钆液闪探测器中的中子俘获时间分布。结果表明,中子俘获时间主要集中在约30us以内,中子俘获平均时间为11us。Background：Gadolinium-loaded liquid scintillator was widely used in the research of nuclear physics,（n,γ） discrimination and distribution of neutron capture time of gadolinium-loaded liquid scintillator were main values of detecting performance.Purpose：This paper attempts to develop the 0.5%wt gadolinium-loaded liquid scintillators with better neutron gamma discrimination factor by measuring the detecting performance of gadolinium-loaded liquid scintillators of several proportion and composition.Methods：The neutron gamma discrimination of gadolinium-loaded liquid scintillator detectors were measured using zero-crossing discrimination.The distribution of neutron capture time was measured for the φ13 cm×30 cm gadolinium-loaded liquid scintillator detector with coincidence method,the start signal was got from fission fragment of 252 Cf fission chamber,the stop signal was got from anode output of gadolinium-loaded liquid scintillator detector.Results：It shows that the best of neutron gamma discrimination can be offered when naphthalene is set with 7.5%wt in the gadolinium-loaded liquid scintillator.The result showed that neutron capture time of the φ13 cm×30 cm gadolinium-loaded liquid scintillator detector was distributed within 30 us,the average time of neutron capture was 11 us.Conclusion：The neutron capture time property of homemade gadolinium-loaded liquid scintillator meets the experiment requirements.

关 键 词：载钆液闪 中子俘获时间分布 裂变电离室 

分 类 号：TL99[核科学技术—核技术及应用]