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Electron Paramagnetic Resonance (EPR) and Thermoluminescence (TL) signals have been studied in samples of Gorilla® Glass (GG) from different smartphones as well as some online stores and vendors. Background, radiation-induced and ultraviolet-induced signals were compared between the samples. Significant variability of both EPR and TL signals (in shape and intensity) was observed between samples from different screens as well as over the surface of the same screen, from the same phone. Both the EPR and TL background signals appear to be due to UV exposure during phone manufacture; some phones have higher EPR and TL signals around the edge of the screen, indicating more UV exposure at the edge than in the center. EPR and TL signals in the same GG samples appear correlated: they decayed over the same temperature region; and both hole- and electron-related EPR and TL signals were made up of stable and unstable components (at room temperature)., (© The Author(s) 2019. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.)

Two different spectra deconvolution methods have been compared on samples of Gorilla® Glass (GG) irradiated in the dose range 0-20 Gy and measured with X-band EPR. The first method used a matrix deconvolution procedure using sample-specific sets of reference signals. The second method used a 'universal' set of eight reference signals (due to five electron centers, two hole centers and a background) to fit EPR spectra from any GG sample. Dose-responses curves were constructed for each individual reference signal. These were then used to test reconstruction of a laboratory-administered dose of 2 Gy. For the matrix method, the values of the reconstructed and nominal doses were within ± 20% after averaging measurements from three aliquots of each sample. For the universal method, the most promising results were obtained with E1, E4 and H1 signals. The fitting failed for one sample, due to dominance of the background signal., (© The Author(s) 2019. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.)