Improved peak shape fitting in alpha spectra

Peak overlap is a recurrent issue in alpha-particle spectrometry, not only in routine analyses but also in the high-resolution spectra from which reference values for alpha emission probabilities are derived. In this work, improved peak shape formulae are presented for the deconvolution of alpha-particle spectra. They have been implemented as fit functions in a spreadsheet application and optimum fit parameters were searched with built-in optimisation routines. Deconvolution results are shown for a few challenging spectra with high statistical precision. The algorithm outperforms the best available routines for high-resolution spectrometry, which may facilitate a more reliable determination of alpha emission probabilities in the future. It is also applicable to alpha spectra with inferior energy resolution. - Highlights: • A new algorithm for analysis of alpha-particle spectra is presented. • The peak shape functions reproduce low- and high-energy tailing. • Its proficiency is demonstrated by a fit to high-resolution spectra. • It outperforms existing specialised fit functions