Use of Neutron Scintillation Detectors as a Substitute for Helium-3 Counters in Radiation Monitors
Use of Neutron Scintillation Detectors as a Substitute for Helium-3 Counters in Radiation Monitors
复制标题
在辐射监测仪中使用中子闪烁探测器替代 He-3 计数器
作者：
E. V. Ryabeva;V. Kadilin;V. A. Idalov
这项工作的目的是分析辐射监测器中探测材料的使用，以及用中子探测闪烁技术取代广泛使用的基于~3H的中子计数器。氦计数器的更换是两个因素的结果：3He的缺乏和3He计数器在安全设备中的广泛使用，如体积中子探测器。这项工作使用了评价有前景的技术的选择标准，具体地说，高的绝对中子探测效率-在20 mm厚的慢化器中在2m的距离内在1秒内探测1 ng 252Cf的效率至少1.5个计数，以及对γ射线探测的低灵敏度-γ-射线探测效率在0.1μSv/hγ射线源照射下不超过10-6。由于闪烁探测器具有较大的灵敏面积和较高的分辨率，现已被提议作为氦计数器的替代品。但有必要找到一种对γ辐射同时具有低灵敏度的最佳闪烁体，并选择一种最佳的信息测量方法。从所提出的问题的观点出发，对基于Li2OSiO_2：Ce~(3+)、LiF/ZnS(Ag+)、Li6Gd(BO_3)_3：Ce、Cs2LiYCl6(Ce)(CLYC)和EJ-254掺硼塑料的潜在中子探测技术进行了评述。
The purpose of this work is to analyze the use of detecting materials in radiation monitors as well as the replacement of widely used 3H-based neutron counters by neutron-detection scintillation technology. The replacement of helium counters is a consequence of two factors: the lack of 3He and widespread use of 3He-based counters in safety equipment, such as volumetric neutron detectors. Selection criteria for evaluating promising technologies are used in this work, specifically, high absolute neutron detection efficiency – efficiency at least 1.5 counts in 1 sec in detecting 1 ng 252Cf at distance of 2 m in a 20 mm thick moderator and low sensitivity to γ-ray detection – γ-ray detection efficiency not exceeding 10–6 with irradiation by a 0.1 μSv/h γ-ray source. Since they can have a large sensitive area and high resolution, scintillation detectors are now being proposed as alternatives to helium counters. But it is necessary to find an optimal scintillator possessing simultaneously low sensitivity to γ-radiation and to choose an optimal method of measuring information. Promising neutron detection technologies based on the glasses Li2OSiO2:Ce3+, LiF/ZnS(Ag+), Li6Gd(BO3)3:Ce, Cs2LiYCl6(Ce) (CLYC) as well as EJ-254 boron-doped plastic are examined from the standpoint of the posed problems.