A method for gamma background subtraction using Visual Basic for Applications code with Microsoft Excel

摘要

This work proposes a method for gamma background subtraction by combining several background spectra acquired during short-term measurements (100,000s). A dedicated Visual Basic code has been developed, that performs an energy correction due to gain drifts, via interpolation of the counts, and finally a summation of several background spectra. Three interpolations were tested: linear, quadratic and cubic, from which the linear was selected after checking the Gaussian fit and accuracy of the areas of the resulting photopeaks. The activity concentration results using the proposed algorithm in two intercomparable exercises and different matrices showed the reproducibility of the proposed method.