X射线管激发X荧光光谱连续本底扣除方法研究

X射线管是目前X射线荧光光谱分析中最常采用的激发源,它所产生的原级谱成为了X荧光光谱中本底成分的主要来源,在对这种光谱进行进一步的分析处理之前需要对其本底进行扣除,对本底估计的准确性直接影响后续处理步骤的效果。对射线管激发X荧光光谱的成分进行了分析,针对其本底特点构造了一种本底强度的估计方法,并根据实测谱线构建了理论测试谱线以便对光谱处理算法的效果进行评价。该方法利用测得X射线荧光光谱中不包含特征峰的谱段对X射线管原级谱造成的本底成分进行估计,使用只包含连续本底的谱段对整个测量谱段进行插值,从而避免了谱线特征峰重叠或对半高宽估计不当时所产生的影响。利用构建的测试光谱对SNIP法、傅里叶变换法和本文的本底估计方法的使用效果进行了比较,使用该方法估计的本底与理论本底更加接近。结果表明使用的方法对X射线管激发的X荧光光谱的本底估计准确,可以采用这种方法对连续本底进行扣除,在对实际测得的X射线荧光光谱的本底扣除中取得了较好的应用效果。

Research on the Background Subtraction Method for X-Ray Fluorescence Spectrum with X-Ray Tube Excitation

X‐ray tube is the most commonly used equipment in X‐ray fluorescence spectrum analysis as excitation source whose primary spectrum has become a major source of the background of X‐ray fluorescence spectrum .Background subtraction should go before further analysis of this spectrum .The accuracy of the estimation of the background directly affect the results of subse‐quent processing steps .In this paper ,the tube excitation component of X fluorescence spectrum is analyzed with an estimation method of background intensity against their background characteristics ,and structuring theoretical spectral lines based on the measured spectral lines in order to evaluate the effect of spectral processing algorithms .The method utilizes the measured X‐ray fluorescence spectrum which does not contain the characteristic peak of the spectrum ,In order to estimate the composition of the original spectrum of the X‐ray tube .It uses the spectrum that contains the continuous background for interpolating the entire measured spectrum ,thereby avoiding overlapping the spectral characteristic peaks or improperly estimating full width at half maximum .This paper compared SNIP ,Fourier transform method and the background subtraction method using the measured spectral lines .Using this method to estimate the background is closer to the theoretical background .The results showe that the method for X‐ray fluorescence spectrum by X‐ray tube excitation is accurate in this article ,this method can be used to deduct continuous background ,and good applied effectiveness has been achieved in the background subtraction of the actually measured X‐ray fluorescence spectrometry .