摘要
对液体闪烁探测器EJ339A中子与伽马辐射测量问题,采用理论模拟与实验分析方法,结合自主设计搭建的基于Lab VIEW的数字化信号处理系统,分别完成22Na、133Ba、137Cs和60Co等4种不同能量的γ源等效电子能量测量与刻度。在此基础上,利用中子飞行时间测量原理,在不同时间窗下将锎(252Cf)源近似分化成若干个单能中子源,获得1.9 7.8 Me V范围内中子在探测器中的光输出响应函数。结果表明,理论模拟与实验测量值在低能段比较吻合,而高能段存在约7.3%的误差。
Background： The light output function is an elementary aspect for neutron spectrometry measured by an organic scintillator to unfold the neutron spectrum from the pulse height distribution. Purpose： This paper aims to investigate the properties of a boron-loaded liquid scintillator EJ339A, using photon sources and neutrons from a 252Cf source. Methods： The light output was defined using Compton electron spectra. Pulse shape discrimination （PSD） and time of flight （TOF） were used to distinguish neutron and γ-rays. Combining theoretical modeling and experimental research, four different gamma sources are applied to achieve equivalent calibration of electronic energy, namely 22Na, 133Ba, 137Cs, and 60Co, respectively. Accordingly, based on TOF method, 25ZCf, a spontaneous fission neutron source, is treated as several quasi-monoenergetic neutron sources under different time-windows. Results： The electron light output scale was calibrated by the measured detector response. Neutrons deposit energy in the detector and give a light output function with the neutron energy in the range of 1.9-7.8 MeV. Conclusion： It shows that experimental data of light output function are in good agreement with simulation result in the low energy section, while discrepancies arise in the high energy section.
出处
《核技术》
CAS
CSCD
北大核心
2016年第5期49-54,共6页
Nuclear Techniques
