锂玻璃探测器辐射特性的试验研究

Experimental Study on Radiation Characteristics of Lithium Glass Detector

锂玻璃中子探测器具有中子探测效率高的特点,尤其在高热中子注量率条件下,能够迅速得到中子通量数据,为脉冲堆等热中子辐射场的中子通量快速测量提供了一种可行的手段。本文用锂玻璃探测器样机对252Cf中子源进行测试,获得了输出的中子脉冲信号,并计算得出对应的中子脉冲信号的平均电荷量。分析结果表明,锂玻璃探头厚度对中子脉冲平均电荷量有影响,且脉冲平均电荷量及光电倍增管(PMT)增益随电压的变化而变化的趋势基本一致,PMT在较高的工作电压条件下测量得到的中子脉冲平均电荷量更为精确,可信度更高。

Lithium glass neutron detector has the characteristics of high neutron detection efficiency, especially under the condition of high thermal neutron fluence rate, it can quickly obtain neutron flux data, which provides a feasible means for fast measurement of neutron flux in the thermal neutron radiation field of pulse reactor. In this paper, a lithium glass detector prototype is used to test the252 Cf neutron source, obtain the output neutron pulse signal, and calculate the average charge of the corresponding neutron pulse signal. The analysis results show that the thickness of the lithium glass probe has an effect on the average charge of the neutron pulse, and the average charge of the pulse and the gain of the photomultiplier tube(PMT) are basically the same with the change of voltage, and the average charge of neutron pulse measured by PMT at higher operating voltage is more accurate and more reliable.