4He闪烁裂变中子探测器时间响应

Time response of helium scintillation fission neutron detector

研制了可用于脉冲辐射场中子探测的4 He闪烁裂变中子探测器,并对其时间响应进行了理论和实验研究。采用经验公式和蒙特卡罗方法模拟计算了不同厚度裂变靶产生的裂变碎片和不同能量中子产生的反冲4 He核在4 He气中的飞行时间,并依据卷积原理推导出探测器的时间响应计算公式。计算结果表明,探测器的波形上升时间约为19.5ns,半高宽约31.0ns。用ING-103型稠密等离子体聚焦装置(DPF)脉冲中子发生器对探测器的时间响应进行了实验测量,实验结果与理论值基本一致。

A new helium scintillation fission neutron detector was designed to detect the neutrons in the mixed pulse fission radiation field. The time response of the detector was investigated through theoretical and experimental methods. The flying time of the fragments and recoiled helium nucleus in helium scintillator were calculated based on the experimental formulae and method of Monte Carlo. The formula of detector＇s time response was deduced from the convolution method. The result of the calculating detector＇s wave indicated that the risetime was about 19.5 ns and FWHM was about 31.0 ns. The time response was measured on the dense plasma focus device（DPF） neutron generator. The theoretical resuhs of time response were consistent with experi- mental results.