Sensitivity and linearity of optical fiber-based neutron detectors using small6Li-based scintillators
Sensitivity and linearity of optical fiber-based neutron detectors using small6Li-based scintillators
复制标题
使用小型 6Li 闪烁体的光纤中子探测器的灵敏度和线性度
DOI：
10.1016/j.nima.2018.11.120
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发表时间：
2020
影响因子：
1.4
通讯作者：
T. Hamano
中科院分区：
文献类型：
--
作者：
A. Ishikawa;A. Yamazaki;Kenichi Watanabe;S. Yoshihashi;A. Uritani;K. Fukuda;A. Koike;R. Ogawara;M. Suda;T. Hamano
我们开发了基于光纤的中子探测器，使用小块的6li基闪烁体，即Eu: licaalf6晶体和liff /Eu: caf2共晶。考虑到这些元素具有高光产率（超过10,000个光子/中子），即使使用光纤光导，它们也可以产生具有清晰峰的脉冲高度光谱。为了调节中子灵敏度，我们控制了闪烁体中6li的含量。我们用Eu: licaalf6和LiF/Eu: caf2制备了三种不同的探测器，并对每种探测器的中子灵敏度进行了评价。该方法证实了中子灵敏度与6li的数量之间存在线性关系，这意味着用高精度天平测量的6li质量可以作为一个很好的中子灵敏度度量。我们还通过使用基于加速器的中子源，检查了探测器在相对高中子通量下输出的线性度。虽然探测器在高计数率下表现出饱和行为，但通过使用不同数量的6li组合多个探测器，我们能够覆盖相对较宽的动态范围。在校正了由于堆积事件引起的脉冲高度失真和计数损失后，我们能够确认检测器的线性，计数率高达100 kcps。
We developed optical fiber-based neutron detectors that use small pieces of6Li-based scintillators, namely, Eu:LiCaAlF6crystals and LiF/Eu:CaF2eutectics. Considering that these elements have high light yields (more than 10,000 photons/neutron), they can produce pulse height spectra with clear peaks even when using optical fiber light guides. To adjust the neutron sensitivity, we controlled the amount of6Li in the scintillator. We fabricated three different detectors using Eu:LiCaAlF6and LiF/Eu:CaF2with various amounts of6Li and then evaluated the neutron sensitivity of each detector. This approach confirmed that there was a linear relationship between the neutron sensitivity and amount of6Li, thus implying that the6Li mass measured by a high-precision balance could be a good metric of neutron sensitivity. We also checked the linearity of the output of the detector at relatively high neutron fluxes by using an accelerator-based neutron source. Although the detectors showed saturation behavior at high count rate, we were able to cover a relatively wide dynamic range by combining multiple detectors using different amounts of6Li. After correcting for the pulse height distortion and count loss due to pile-up events, we were able to confirm the linearity of the detectors up to a count rates of 100 kcps.