闪烁体光纤探测器是近年来发展起来的一种可用于中子测量的新型探测器，为了提高闪烁体光纤探测器的中子探测效率，该文以232Th+ZnS（Ag）为探测器材料，利用波长位移光纤代替普通光纤收集和传输信号，并对改进的探测器的探测效率进行了理论分析和实验验证。研究结果表明：波长位移光纤探测器的计数率约为普通光纤的1.7倍。该探测器应用于加速器驱动次临界系统的中子探测，获得了次临界反应堆实验装置中子的分布变化规律，与计算结果较为一致。
Optical fiber scintillator neutron detectors have developed rapidly in recent years because these detectors are small (so that they can be extended into narrow spaces) and give real-time measurements. However, the probe detection efficiency is low due to the small size of the probe's effective detection material. This study presents a theoretical and experimental study of a 232Th+ ZnS(Ag) neutron detector with a wavelength-shifting fiber was used to improve the detection efficiency. This detector was used to measure the neutron distribution of the ADS sub-critical experimental assembly with the measurement results being consistent with the theoretical model which indicates that the high detection efficiency is very good and the wavelength-shifting fiber neutron detector is accurate.
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