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Simulation studies of thermoluminescence (TL) and other stimulated luminescence phenomena are a rapidly growing area of research. The presence of competition effects between luminescence pathways leads to the complex nature of luminescence signals, and therefore, it is necessary to investigate and validate the various methods of signal analysis by using simulations. The present study shows that in simulations of luminescence signals originating from multilevel phenomenological models, it is not possible to extract mathematically the individual information for each peak in the signal. It is further shown that computerized curve deconvolution analysis is the only reliable tool for extracting the various kinetic parameters. Simulation studies aim to explain experimental results, and therefore, it is necessary to validate simulation results by comparing with experiments. In this paper, testing of simulation results is performed using two methods. In the first method, the influence of competition effects is tested by comparing the input model parameters with the output values from the deconvolution analysis. In the second method, the agreement with experimental results is tested using the properties of well-known glow peaks with very high repeatability among TL laboratories, such as the 110 °C glow peak of quartz.

The thermoluminescence (TL) method is one of the most widely used techniques in various studies, including dosimetric applications, dating of archaeological and geological materials, luminescence spectroscopy of certain insulating or semiconducting phosphors, and the detection of ionizing radiation damage. This study examines the TL properties of plagioclase, a feldspar group mineral, focusing on its dose–response behavior, kinetic parameters, and glow curve characteristics. TL measurements of plagioclase samples were carried out with different ionizing radiation doses ranging from 0.1 to 550 Gy. The results show a strong linear dose–response relationship in the 0.3–550 Gy range, with no evidence of saturation or supralinearity. A computerized glow curve deconvolution (CGCD) analysis revealed that the TL glow curve of the mineral consists of five distinct TL peaks with activation energies ranging from 0.842 eV to 0.890 eV and obeying general order kinetics. In addition, an artificial neural network (ANN) model was developed to predict TL glow curves using three optimization algorithms, including Levenberg–Marquardt (LM), Bayesian Regularization (BR), and Scaled Conjugate Gradient (SCG). Among these, the BR algorithm demonstrated the best performance with an accuracy value of 0.99915, a Mean Absolute Error (MAE) of 2.34 × 10−3, and a Mean Squared Error (MSE) of 3.82 × 10−5, outperforming LM and SCG in in terms of generalization and accuracy. The findings of this study demonstrate the effectiveness of combining TL analysis with ANN-based modelling for accurate dose–response predictions and the improved luminescence characterization of plagioclase, supporting the applications of luminescence studies in radiation dosimetry and geochronology.

Thermoluminescent dosimeters (TLD) and optically stimulated luminescent dosimeters (OSLD) are practical, accurate, and precise tools for point dosimetry in medical physics applications. The objective of this study is to investigate the luminescence properties—both OSL and TL—of lithium fluoride (LiF) doped with magnesium (Mg), copper (Cu), and phosphorous (P) (LiF: Mg, Cu, P), commercially known as TLD-100H. The goal is to devise a methodological approach for dose measurement that allows for obtaining two independently measured dose values at each irradiation point, thereby improving accuracy and precision. The luminescence properties of TLD-100H were studied using a beta irradiation source (90Sr/90Y) integrated into the TL/OSL DA-15 automated Risø reader. This study identified the ideal experimental conditions for optimal dose evaluation and used them for dosimeter calibration across doses ranging from 0.5 to 4.0 Gy. The results demonstrated that, under optimal measurement parameters, the OSL and residual thermoluminescence (ResTL) signals—correlated to two trap systems within the dosimeter—exhibited high reproducibility, stability over multiple cycles, and high precision and accuracy (≤2%). Specifically, the OSL response showed good linear behavior across the investigated dose range, while the ResTL signal exhibited linear behavior between 0.5 and 2 Gy and sublinear behavior for doses >2 Gy.

The stability of glow peaks in [sup.6]LiF:Mg,Ti (TLD-600) exposed to a high-energy Fe-ion beam was examined in comparison to [sup.137]Cs [gamma]-ray irradiation under changing annealing conditions. The peak areas induced by the Fe ions were much smaller than those by [gamma]-rays. The sizes and positions of peaks 3-5 in Fe-ion irradiated samples were hardly changed after post-annealing at 100°C×30 min, regardless of the pre-annealing conditions (fast quenching or subsequent pre-annealing at 100°C×2h). Whereas, the peaks in [gamma]-ray irradiated samples were notably affected by post-annealing; the peak positions and peak-area sizes changed in different ways depending on the pre-annealing conditions. The effects of post-annealing on peak 6 were identical for Fe ions and [gamma]-rays. These facts suggest that peaks 3-5 in TLD-600 comprised both stable and unstable luminescent centers, and that the latter part would be easily depleted in highly dense ionization. Keywords: thermoluminescent detector, LiF:Mg,Ti, glow curve deconvolution, annealing, NIRS-HIMAC

The stability of glow peaks in 6LiF:Mg,Ti (TLD-600) exposed to a high-energy Fe-ion beam was examined in comparison to 137Cs γ-ray irradiation under changing annealing conditions. The peak areas induced by the Fe ions were much smaller than those by γ-rays. The sizes and positions of peaks 3-5 in Fe-ion irradiated samples were hardly changed after post-annealing at 100°C×30 min, regardless of the pre-annealing conditions (fast quenching or subsequent pre-annealing at 100°C×2h). Whereas, the peaks in γ-ray irradiated samples were notably affected by post-annealing; the peak positions and peak-area sizes changed in different ways depending on the pre-annealing conditions. The effects of post-annealing on peak 6 were identical for Fe ions and γ-rays. These facts suggest that peaks 3-5 in TLD-600 comprised both stable and unstable luminescent centers, and that the latter part would be easily depleted in highly dense ionization.

This chapter contains sections titled: Deconvolution Monte‐Carlo Methods Genetic Algorithms Application of Differential Evolution to Fitting OSL Curves

The exact equations of the thermoluminescence (TL) glow curve deconvolution that describe the intensity of a single TL glow peak of different order kinetics, which are obtained from the one trap-one recombination (OTOR) level model, are considered. The reformulation of the expressions of the intensities of TL glow peaks in terms of the peak intensity IM, peak position TM, and the activation energy ∈, for each order of kinetics are achieved. The authors developed a MATLAB computer code, which utilizes the obtained equations, to computationally deconvolute the TL glow curves. The code is used to investigate the reference glow curves of the GLOCANIN program. The obtained results agree with those previously reported by the GLOCANIN project with better values of the figure of merits FOM. The considerations of the obtained equations show promising trends to understand a peak formation for different order kinetics that belong to the OTOR level model.

For decades, the deconvolution analysis of the thermoluminescence glow curve has been assessed using the figure of merit (FOM). In the present study, it has been shown that the FOM is not sufficient to assess the deconvolution analysis of TL glow curves. An alternative criterion has been proposed based on the uncertainty of the deconvolution analysis. A comparison between the proposed criterion and the FOM was conducted using theoretical simulations and experimental results. It has been shown that the developed criterion can provide detailed information about the fitting quality for each region in the glow curve as well as give an overall assessment of the deconvolution process. The uncertainty of deconvolution analysis using the general-order kinetics has been estimated for various glow curves. The TL-SDA toolkit has been updated to include the feature of evaluating the uncertainty of the deconvolution process.

Within the framework of the one trap-one recombination (OTOR) level model, a new software was designed to deconvolute the thermoluminescence glow-curves. The computer code was written considering deconvolution equations obtained, without any approximations, from the (OTOR) model with free parameters TM, IM, and ε. The code can also use the original equations of the OTOR model with free parameters s, ε, n o , and β. The new software was applied to deconvolute glow curves measured from irradiated in-house prepared Al 2 O 3 doped with Cr 2 O 3 dosimeters. The consequences of the deconvolution analyses of the reference glow curves agree with those reported in the literature.

Thermoluminescence (TL) glow curves of CaSO 4 :Dy phosphor were analyzed using a recently formulated simplified general one-trap (GOT) equation. The phosphor's activation energy (E) and frequency factor (s) were in the range of 1.014–1.421 eV and 10 9 to 10 11  s −1 , respectively. Furthermore, the analysis of the TL curve in the new simplified GOT equation provided information on the behavior of the empty traps and how they influence the retrapping process. The analysis of the TL curve in the simplified GOT equation shows that about 32–65% of the empty traps of the main dosimetric peak of CaSO 4 :Dy phosphor participate in the retrapping process, which is an essential requirement of a dosimetric peak. This vital information was missing in the previously reported TL analysis of the CaSO 4 :Dy phosphor.