New articles published: V. 13 n. 4 (2025)

Applying Deep Learning in gamma-spectroscopy for radionuclide identification

Abstract: This study presents the results of using a Deep Convolutional Neural Network model on gamma spectrum classification for radioactive waste management. The approach uses a modified version of the VGG-19 architecture, originally developed for image recognition with 1000 mutually exclusive classes. The modified VGG-19 architecture uses a gamma spectrum as input and classifies, on a nonexclusive basis, ten classes representing the ten most common radionuclides at IPEN's Radioactive Waste Management Department (Am-241, Ba-133, Cd-109, Co-57, Co-60, Cs-137, Eu-152, Mn-54, Na-22, Pb-210). Gamma spectra were generated using Monte Carlo simulations created with PENELOPE/PenEasy, simulating an HPGe detector with sources inside a steel drum filled with paper, representing the common content of the drums managed at IPEN's Radioactive Waste Management Department. The data set was augmented by mixing these simulated spectra into new spectra containing up to four radionuclides. Several distances from the detector to the drum (41 cm, 46 cm, 51 cm, and 56 cm) were used to create a representative data set. The data from 56 cm (originally 150 spectra after the argumentation process, 375 spectra) was used for validation. After 250 training epochs, the model achieved consistent performance in the training set, demonstrating the efficiency of the method. Read full article.