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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.

The dosimetric properties of synthetic ZnO/Ag/ZnO multilayer film are investigated. The proposed dosimeter was prepared by radio frequency and direct current RF/DC sputtering and irradiated with X-ray doses up to 4 Gy. The properties of thermoluminescence (TL) such as glow curve, dose-response, homogeneity batches, sensitivity, minimum detectable dose (MMD), precision, kinetic parameters (activation energy E , frequency factor S ), and percentage depth dose (PDD) were studied. The thin film appeared to have an excellent linear response, and the sensitivity was almost twice the commercial TLD. The readout of the homogeneity and PDD are the same properties of TLD-100. These desirable qualities demonstrated the versatility of this novel synthetic thin film in applications involving radiation detection.

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.

In this study, the thermoluminescence characteristics of naturally occurring salt (NaCl) were assessed for the development of a radiation dosimeter. For this purpose, mined crystalline samples of salt were procured directly from Khewra salt mines in Pakistan. The samples were hand crushed, sieved, and compressed to pellets comparable in size to standard TLD chips, and irradiated to gamma radiation doses in the range of 5 mGy and 5000 mGy. Thermoluminescence (TL) response showed three main peaks in the glow curve around 115–130 °C, 150–170 °C, and 220–240 °C. A linear TL response was observed for the dose range of 5–100 mGy. The TL response became supra-linear for the dose ranges of 100–1000 mGy and 1000–5000 mGy. The Tm-Tstop method was applied to identify the overlapping peaks of the glow curve. Computerized glow curve deconvolution (CGCD) was then employed for the characterization of electron trap parameters such as frequency factor (s), activation energy (E), and the kinetic order (b), using General Order (GO) kinetics. The figure-of-merit (FOM) was found to be 1.08%, 0.94%, 0.77%, and 0.75%, at 500 mGy, 1 Gy, 2 Gy, and 5 Gy, respectively. The TL intensity faded by 20% within the first 24 h after irradiation and finally stabilized after two weeks. In addition, structural, morphological, and elemental analyses, were also performed using various analytical techniques. X-ray diffraction (XRD) showed that the salt crystallizes in a face-centered cubic structure. Scanning electron microscope (SEM) micrographs indicated that the crystallites are closely packed and cubic-shaped with non-uniform size, and mostly found in the agglomerated form. Similarly, the elemental analysis confirmed the presence of impurities such as Mg, Sr, S, K, O, and Ca, in the samples. The present study concludes that the pellets made from salt samples from Khewra mines have a potential for use as radiation dosimeters.

This study investigated natural sand thermoluminescence (TL) response as a possible option for retrospective high-dose gamma dosimetry. The natural sand under investigation was collected from six locations with selection criteria for sampling sites covering the highest probability of exposure to unexpected radiation on the Egyptian coast. Dose-response, glow curve, chemical composition, linearity, and fading rate for different sand samples were studied. Energy Dispersive X-ray Spectroscopy (EDX) analysis revealed differences in chemical composition among the various geological sites, leading to variations in TL glow curve intensity. Sand samples collected from Ras Sedr, Taba, Suez, and Enshas showed similar TL patterns, although with different TL intensities. Beach sands of Matrouh and North Coastal with a high calcite content did not show a clear linear response to the TL technique, in the dose range of 10 Gy up to 30 kGy. The results show that most sand samples are suitable as a radiation dosimeter at accidental levels of exposure. It is proposed here that for high-dose gamma dosimetry with doses ranging from 3 to 10 kGy, a single calibration factor might be enough for TL measurements using sand samples. However, proper calibration might allow dose assessment for doses even up to 30 kGy. Most of the investigated sand samples had nearly stable fading rates after seven days of storage. The Ras Sedr sands sample was the most reliable for retrospective dose reconstruction.

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.

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.

In the present work, the Thermoluminescence (TL) properties of red sand sample collected from Nasr city, Cairo, Egypt was studied (the grain size effect, glow curve properties, dose response, batch homogeneity and fading). Surface morphology was studied using scanning electron microscopy (SEM). Chemical compositions of the red sand samples were estimated using X-ray fluorescence (XRF) machine. The analysis showed that the red sand sample mainly consisted of SiO 2 (95.84%) and has feldspar which exhibits thermoluminescence. The experimental results illustrated that the optimum grain size ranges from 75 to150μm. After irradiation with γ-source (Co-60), the glow curves of the sample were found to have three peaks. The response curve has linearity in the dose range 10Gy – 2 kGy. Through 100 day, the total TL-signal fading reached 17%, but the dosimetric peak reached 12%. The measured activation energies of the peaks were deep enough to store the TL-signal. The pre-irradiation annealing at 800 °C for 1 h increased the TL sensitivity 2.295 times its original value. It could be concluded that the investigated samples could be used in environmental high γ-radiation measurements.

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.

In this study, the thermoluminescence dosimetric performances of a locally produced soda–lime–silica glass by the Saudi Arabian Glass Company Limited (SAGCO) were examined to evaluate its potential use in low-dose γ-ray field. The samples were homogenously irradiated to different doses using a cesium-137 source. Some important characteristics of these glass dosimeters were investigated: The thermoluminescent glow curve exhibited a main peak at about 200 °C, the dose response curve showed a good linearity in the low-dose range 0–500 mGy, and the lowest detection dose was found to be 0.30 mGy. No substantial change (less than 6%) in the response of the dosimeters was found within incident angles of irradiation between ± 60°. A post-irradiation heating at 160 °C for 15 min before readout was found to be the most appropriate procedure for the elimination of the initial rapid fading.