Photopeak detection and quantification using wavelet analysis

Abstract

Automated isotope identi cation has long been an important problem in homeland security and nuclear emergency response. This process is di cult for low-resolution spectra because of the presence of the Compton contin- uum, electronics noise, and peak overlap. The wavelet transform stands out among many potential solutions of this problem, owing to its ability to de-noise noisy signals, pattern matching, and simultaneous multi-resolution signal analysis. In this thesis, a novel wavelet-based algorithm for detecting peaks and measuring their areas is introduced. Its abilities in locating peaks, resolving overlapping peaks, and determining peak areas are presented and assessed with both simulated signals and real gamma-ray spectra. Peak area uncertainty was explored and future work and directions were discussed at the end.