## 3 Results and Discussions
### Dose Response  
Luminescent materials, particularly insulators and semiconductors, play a crucial role in different dosimetric and spectroscopic applications. Thermoluminescence (TL) is a key parameter for evaluating the dose responses of both natural and synthetic materials to ionizing radiation [1; 3]. The dose response refers to the relationship between the absorbed radiation dose and the intensity of the TL signal emitted when the material is heated [1]. However, some materials exhibit supralinearity or saturation at higher doses due to the limitations of trap filling and recombination mechanisms within their crystal structure [2]. The TL method provides insights into the kinetics of trapping and recombination processes, enabling the optimization of materials for specific applications [3; 4]. In summary, understanding the dose response of luminescent materials is a cornerstone of TL research. The response of the material to the ionizing radiation doses determines its place in a wide range of applications.  
In this study, dose-response experiments, which are essential for research using the TL method, were performed on the plagioclase mineral over a wide dose range (from 0.1 Gy to 550 Gy). A number of selected TL glow curves obtained from the dose-response experiments are shown in Figure 2.  
Figure 1: SEM/EDS analysis results for the plagioclase mineral.  
Figure 2 illustrates the TL glow curves of the plagioclase mineral plotted as a function of temperature for various radiation dose values. As can be seen in Figure 2, there is no observed change in the shape of the TL glow curves with increasing dose. In addition, it is observed that both the areas under the glow curves and the peak heights (TL signals) increase with increasing dose. This increase in TL intensity with increasing dose is a well-documented phenomenon in the literature and is primarily attributed to the higher density of charge carriers trapped in luminescence centers (electron traps) as the dose increases. This relationship has been extensively studied and is often described as linear within a certain dose range, followed by potential supralinearity or saturation at higher doses due to limitations in trap filling or recombination dynamics [1,2]. Studies have shown that materials such as plagioclase and LiF:Mg,Ti exhibit a predictable increase in the TL signal under low-to-moderate doses, making them suitable for dosimetric applications [3,4]. The proportional increase in TL intensities with dose is often linked to the growing number of excited electrons captured in the traps, which release their energy as luminescence during heating [2,27].  
The areas under the TL radiation curves are plotted as a function of each ionizing radiation dose on a log-log scale, as shown in Figure 3. For each dose value, a data point represents the mean value of the TL measurements obtained from five identical rimmed discs, and the error bars represent the standard deviation.  
Figure 3: Response of the TL peak area for the plagioclase to the dose of ionizing radiation.  
Figure 2: TL glow curves of plagioclase mineral at (**a**) 0.1–80 Gy and (**b**) 80–550 Gy beta radiation dose ranges.  
As can be seen in the graph of peak areas versus radiation dose shown in Figure 3, it can be said that there is a very good linear response between total TL intensity and radiation doses in the dose range of 0.3 Gy to 550 Gy. No radiation damage was observed on the material within the measured dose ranges, nor were any supralinear, sublinear, or saturation dose-response regions detected.