An Integrated Single-Step Gamma Spectrum Analysis Method Based on Bregmanized Variational Deconvolution

Gamma spectrum analysis is an important technique in many radiation measurement contexts. Current gamma spectrum analysis consists of several separate procedures such as linear smoothing and peak fitting. Although widely used, this routine may give incorrect results when the peak is weak or when several peaks are overlapped together. This problem becomes more severe if the statistical fluctuation of the spectrum is large. To simultaneously resolve overlapping peaks and reduce fluctuations, an integrated gamma spectrum analysis method that can obtain peak information of gamma spectrum in a single step was proposed in this study. The proposed method models both physical modulation of gamma spectrometer and the statistical fluctuations into a single linear equation, and converts the gamma spectrum analysis into an inverse problem. Bregman iteration and total variation regularization are utilized to solve this inverse problem under the framework of variational deconvolution, so that the true spectrum can be directly obtained. The feasibility and performance of the proposed method was evaluated by both numerical simulation experiment and Monte Carlo simulation experiment. The experiment results demonstrate that the proposed method can simultaneously resolve overlapping peak and reduce the fluctuations in gamma spectra while preserves both qualitative and quantitative peak information precisely. The proposed method may provide a new way for the development of gamma spectrum analysis method.