Pritchard K, Hussey D, Osovizky A, Ziegler J, Binkley E, Tsai P, Hadad N, Jackson M, Hurlbut C, Baltic G M, Majkrzak C F, Maliszewskyj N C
NIST Center for Neutron Research, Gaithersburg, MD, United States of America.
NIST Physical Measurement Laboratory, Gaithersburg, MD, United States of America.
Nucl Instrum Methods Phys Res A. 2021 Jan;986. doi: 10.1016/j.nima.2020.164808.
A LiF:ZnS(Ag) based cold neutron detector with wavelength shifting (WLS) fibers and SiPM photodetector was developed at the NIST Center for Neutron Research for the CANDoR instrument (Chromatic Analysis Neutron Diffractometer or Reflectometer). A series of detectors were irradiated with neutron doses ranging between 1E+11 n/cm to 6E+12 n/cm. It was found that the neutron absorbing Li isotope was not measurably depleted, but the photonic yield of the detector deteriorated with increasing neutron dose. Photonic yields were compared before and after neutron exposure by comparing pulse energy spectrum photopeaks before and after exposure. A typical detector used in the CANDoR instrument is expected to withstand a cumulative cold neutron dose of at least 1E+12 n/cm before degrading to an unfit state. The component parts of the detector could not be separated, so the degradation of the bulk scintillator and WLS fibers could not be gauged separately.
美国国家标准与技术研究院中子研究中心为CANDoR仪器（彩色分析中子衍射仪或反射仪）研制了一种基于LiF:ZnS(Ag)的带有波长转换（WLS）光纤和硅光电倍增管（SiPM）光电探测器的冷中子探测器。一系列探测器受到了1E+11 n/cm至6E+12 n/cm范围内的中子剂量照射。结果发现，吸收中子的锂同位素没有明显消耗，但探测器的光子产额随着中子剂量的增加而恶化。通过比较曝光前后脉冲能谱的光电峰，对中子曝光前后的光子产额进行了比较。预计CANDoR仪器中使用的典型探测器在降解到不适用状态之前能够承受至少1E+12 n/cm的累积冷中子剂量。探测器的组成部分无法分离，因此无法分别测量大块闪烁体和WLS光纤的降解情况。
