Abstract:
Background Precise γ-ray spectrum analysis is essential for nuclide identification and activity quantification, but faces significant challenges when using low-resolution detectors such as CLYC scintillators in complex radiation fields. The limited energy resolution of these detectors often leads to overlapping peaks and obscured characteristic spectral features, which complicates accurate spectrum interpretation.
Purpose This study aims to overcome the inherent energy resolution limitations of CLYC detectors by developing a spectrum deconvolution method that can recover clear spectral information and separate overlapping peaks in complex γ-ray spectra.
Methods A detector energy response matrix was constructed by combining Monte Carlo simulations to calculate γ-ray energy response functions with an interpolation method. Response functions were derived across the 0~3 MeV energy range at intervals of 0.05 MeV to ensure high precision. Spectrum deconvolution was then performed using the Maximum Likelihood Expectation Maximization (MLEM) algorithm, which was then applied to analyze the original complex spectrum.
Results The method was validated by unfolding the spectra of a 226Ra source, a mixed 60Co - 137Cs source, and the complex spectrum of 152Eu. The unfolded spectrum exhibited well-resolved characteristic peaks, effective separation of severely overlapping spectral regions, and stable quantitative results for characteristic peak areas.
Conclusions The proposed approach significantly enhances the precision of γ-ray spectrum analysis with CLYC detectors. It successfully reveals the energy and intensity information of incident γ-rays, mitigates the detector’s resolution limitations, and provides a reliable method for analyzing spectrum in complex radiation environment.