Aninversion decomposition method for better energy resolution of NaI(Tl)scintillation detectors based on a Gaussian response matrix
Aninversion decomposition method for better energy resolution of NaI(Tl)scintillation detectors based on a Gaussian response matrix
复制标题
基于高斯响应矩阵的NaI(Tl)闪烁探测器能量分辨率反演分解方法
DOI：
10.1007/s41365-016-0062-1
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发表时间：
2016
影响因子：
2.8
通讯作者：
YU Congcong
中科院分区：
文献类型：
--
作者：
HE Jianfeng;YANG Yaozong;QU Jinhui;WU Qifan;XIAO Hailing;YU Congcong
NaI(Tl)闪烁探测器具有探测效率高、价格低廉等优点，在伽马能谱测量中得到了广泛应用。然而，缓解这些探测器有限的能量分辨率仍然是一项迫切的需要，因为这有损于对所获得的仪器光谱的准确分析。根据NaI(Tl)闪烁探测器的物理性质和光谱形成过程，探测器对不同能量的伽马光子的响应可以用具有唯一全半高宽(FWHM)值的近似高斯形状的光斑来表示。半高宽被建立为基于分辨率校准的探测器参数，并用于构造通用的高斯响应矩阵，该矩阵用于对从探测器获得的伽马能谱进行逆分解。利用Gold和Boost Gold迭代算法加速了测量光谱的分解。对多个模拟重叠峰和实验获得的U、Th放射性核素系列谱进行了逆分解试验，验证了该方法的实用性，特别是在谱的低能区，提供了准确的放射性核素的定性和定量分析。
NaI(Tl) scintillation detectors have been widely applied for gamma-ray spectrum measurements owing to advantages such as high detection efficiency and low price. However, the mitigation of the limited energy resolution of these detectors, which detracts from an accurate analysis of the instrument spectra obtained, remains a crucial need. Based on the physical properties and spectrum formation processes of NaI(Tl) scintillation detectors, the detector response to gamma photons with different energies is represented by photopeaks that are approximately Gaussian in shape with unique full-width-at-half-maximum (FWHM) values. The FWHM is established as a detector parameter based on resolution calibrations and is used in the construction of a general Gaussian response matrix, which is employed for the inverse decomposition of gamma spectra obtained from the detector. The Gold and Boosted Gold iterative algorithms are employed to accelerate the decomposition of the measured spectrum. Tests of the inverse decomposition method on multiple simulated overlapping peaks and on experimentally obtained U and Th radionuclide series spectra verify the practicability of the method, particularly in the low-energy region of the spectrum, providing for the accurate qualitative and quantitative analysis of radionuclides.