常态中子深度分析物理模型

Physical model of neutron depth profiling in common conditions

带电离子在样品内输运过程中的能量岐离、探测立体角有效范围及探测系统噪声都将改变中子深度分析(NDP)的多道离子能谱分布。假定上述三种因素导致的离子探测谱能量展宽都可以采用高斯函数描述,基于一般条件下的NDP装置设计,建立了预测一定深度核素产生的离子测量谱的探测器响应函数物理模型。该模型的理论分析结果与实验测量能谱的峰位、半高宽均符合良好,能够作为中子深度分析测量谱反演分析的基础。

In neutron depth profiling（NDP）, the recorded ions have a spread of energies because of energy straggling, geometrical acceptance angles and detector energy resolution effects. In common conditions, a physical model predicting the observed energy spectrum of a sample with target nuclide in prearranged depth changes is built on the basis of Gaussian function. The pre- dicted ion spectrum derived from the above model is well accorded with the observed energy spectrum in peak position and FWHM. So the model can be applied to deconvolution of NDP spectra.