Research On The Application Of Digital Sallen-key In Nuclear Energy Spectrum Data Processing

As one of the most advanced techniques of modern science and technology,nuclear spectrum measurement and analysis technology has been widely used in all walks of life.With the rapid development of energy spectrum analysis technology,accurate analysis and processing for energy spectrum data becomes more and more important.Due to the randomness and statistical nature of a large number of data in the process of nuclear radiation detection and energy spectrum analysis,a rapid and accurate processing of the original data has become an important prerequisite for qualitative and quantitative analysis of nuclear spectrum.In view of this,based on the investigation of a large number of nuclear spectrum data processing methods,depending on the digital Sallen-Key filter circuit,this paper builds a multi-parameter recursive function model.Rely on the filter forming characteristics of nuclear pulse by Sallen-Key filter,the application of Sallen-Key filter in nuclear spectrum data processing is studied as follows:(1)By using the kirchhoff’s law,the paper analysis the digital Sallen-Key filter circuit,Also,by use numerical analysis method to derive the functional relationship of the model containing multiple parameters(k,m,n,D),then,convert the recursive function into the frequency domain to obtain the amplitude-frequency response function,and analyze the performance and rationality of the model.(2)The multi-parameter recursive function model is applied to the smoothing processing of nuclear energy spectrum,and the influence of various parameters on the smoothing effect is emphatically studied.Taking Fe characteristic X-ray energy spectrum as the smoothing object,the peak shape,peak position,peak area,half-height and half-width of the nuclear energy spectrum after smoothing under different parameters were calculated and analyzed.The effect and influence degree of each parameter on the smoothing of energy spectrum are summarized.The function relation between the peak offset and the parameter change after smoothing is fitted by the method of multiple linear regression,and the peak position correction is simply realized by this function.(3)By analogying the evaluation method of forming effect of nuclear pulse signal,the paper defines two evaluation factors to evaluating the smoothing effect of the model:symmetry parameter and signal-to-noise ratio parameter.Using two evaluation factors,combining with the degree of influence of the parameters on the smoothed energy spectrum,it is obtained: Under this model,the optimal smoothing parameters of Fe characteristic X-ray spectrum are k=1.1,m=2,n=1.5,D =1.05.(4)The smoothing effect of the multi-parameter recursive function model on the energy spectrum is compared with the smoothing effect of the gravity center method,the polynomial moving smoothing method and the Fourier transform method,and the results show that the model has the advantages of good smoothing effect,strong adaptability and remarkable gaussian characteristics of the spectrum peak after smoothing.In view of this,this model can be extended to nuclear energy spectrum data processing.