基于信号功率谱梯度分析的n-γ甄别方法研究

发现了液体闪烁体探测器在分别与中子和γ射线作用时输出脉冲的功率谱梯度存在较大差异这一特征，由此提出一种基于脉冲信号的频域特征参数来甄别中子和γ射线的方法--功率谱梯度分析（SGA）法。本文论述了SGA法的基本原理及其可行性，并通过伴随粒子中子飞行实验验证了SGA法n-γ甄别结果的正确性。研究了SGA法在采样率从5 G/s逐步递减到250 M/s下甄别性能的变化。结果表明，与基于时域特征的n-γ甄别方法相比，SGA法对噪声较不敏感，抗干扰能力强，甄别性能更为稳定且计算量小。

Research on n-γ Discrimination Method Based on Spectrum Gradient Analysis of Signals

Having discovered that there are distinct differences between the spectrum gradient of the output neutron and γ-ray signal from liquid scintillator detectors, this paper presented a n-γ discrimination method called spectrum gradient analysis (SGA) based on frequency-domain features of the pulse signals. The basic principle and feasibility of SGA method were discussed and the validity of n-γ discrimination results of SGA was verified by the associated particle neutron flight experiment. The discrimination performance of SGA was evaluated under different conditions of sampling rates ranging from 5 G/s to 250 M/s. The results show that SGA method exhibits insensitivity to noise, strong anti-interference ability, stable discrimination performance and lower -amount of calculation in contrast with time-domain n-γ discrimination methods.