A Compact Dual Gamma Neutron Detector Based on NaI(Tl+Li) Scintillator Readout with SiPM
A Compact Dual Gamma Neutron Detector Based on NaI(Tl+Li) Scintillator Readout with SiPM
复制标题
基于 NaI(Tl Li) 闪烁体读出和 SiPM 的紧凑型双伽马中子探测器
DOI：
10.3390/cryst12081077
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发表时间：
2022
期刊：
影响因子：
2.7
通讯作者：
Wei Wang
中科院分区：
文献类型：
--
作者：
Fengzhao Shen;Qibin Fu;Tuchen Huang;Wei Wang
铊锂共掺杂的碘化钠晶体是一种很有前途的双伽马中子探测闪烁体，具有广阔的应用前景。在本研究中，基于2英寸NaI(Tl+Li) （NaIL）闪烁体读数和8 × 8硅光电倍增管（SiPM）阵列，开发了一种紧凑型伽马/中子探测器。为SiPM阵列开发了专用的跨阻放大电路。对SiPM阵列的能量分辨率和响应线性度进行了评估，并与光电倍增管读出的能量分辨率和响应线性度进行了比较。SiPM阵列和PMT对661.6 keV伽马射线的能量分辨率分别为7.0%和6.5%。在~4 MeV的能量范围内，SiPM阵列的线性响应与PMT几乎相同。通过数字化仪（12位/250 MSPS）采集脉冲波形和离线分析，评估中子和伽马脉冲形状判别。优化后的SiPM阵列的最佳性能值（FOM）为3.75，接近PMT （FOM = 4.07）。实验结果表明，采用SiPM阵列的NaI闪烁体读数具有与NaI（Tl）伽玛探测器相当的能量分辨率和优异的中子/伽玛分辨能力，特别适用于需要伽玛和中子双重探测能力的小型设备。
Sodium iodide crystal co-doped with thallium and lithium is a promising scintillator with wide application prospects for dual gamma neutron detection. In this study, a compact gamma/neutron detector was developed based on 2-inch NaI(Tl+Li) (NaIL) scintillator readout with 8 × 8 silicon photomultiplier (SiPM) array. Dedicated transimpedance amplifier circuit was developed for the SiPM array. The energy resolution and response linearity with the SiPM array were evaluated and compared to those obtained with photomultiplier tube (PMT) readout. The energy resolution for 661.6 keV gamma rays was measured as 7.0% and 6.5% with SiPM array and PMT, respectively. The linear response of the SiPM array is almost the same as that of the PMT in the energy range up to ~4 MeV. Neutron and gamma pulse shape discrimination was evaluated by acquiring the pulse waveforms with a digitizer (12 bit/250 MSPS) and off-line analysis. The best figure of merit (FOM) was measured as 3.75 for the SiPM array with optimized parameters, close to the performance measured with PMT (FOM = 4.07). The experimental results show that the NaIL scintillator readout with SiPM array exhibit energy resolution equivalent to NaI(Tl) gamma detectors and excellent neutron/gamma discrimination, making it especially suitable for compact devices requiring gamma and neutron dual detection capabilities.