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The quest to identify low-cost thermoluminescence (TL) materials is vital, and the identification and assessment of natural materials suitable for radiation detection is a rapidly growing area of research. In addition to their specific dosimetric characteristics, such materials must be rigid, insoluble, and chemically inert. One such promising low-cost material can be a limestone having vast deposits in Pakistan. The present study reports the TL and dosimetric features of Pakistani limestone pellets and their comparison with TLD-100. The quarried crystalline limestone rock was hand crushed, sieved, and compressed into the standard TLD chip-sized pellets. The TL response, kinetic parameters, batch homogeneity, dose linearity, individual sensitivity correction factor (i.e., elemental correction coefficient ECC), lowest detectable dose limit (LDDL), coefficient of variation (COV), energy dependency, and fading were determined, and compared with TLD-100. For TL analysis, the pellets were exposed to an 8 Gy dose of 250 kVp X-rays. These exhibited complex TL showing four peaks (P1: 90–110 °C, P2: 130–170 °C, P3: 240–280 °C and P4: 320–350 °C). The limestone response was linear in the studied dose range of X-rays (1–10 Gy), unlike the supra-linear behavior of TLD-100. The kinetic parameters (i.e., the frequency factor (f), activation energy (E), and the kinetic order (b)) were estimated through computerized glow curve deconvolution using the general order of kinetics while confirmed by the T m -T stop method. The values of E and f were observed in the ranges of 0.85–1.27 eV and 5.98 × 107 to 1.81 × 1013 s−1, respectively. The calculated value of figure-of-merit (FOM) (i.e., 2.37%) showed a good agreement between the experimental and fitted glow curves. The overall variation in the ECCs for TLD-100 and limestone was found within ±4% and ±7%, respectively. The results of the ECC confirmed batch homogeneity. The calculated value of LDDL was ∼1.01 Gy. The investigation found that the maximum variation in normalized intensity and COV was within the tolerance limit of 5%. The limestone pellets showed less sensitivity than TLD-100. Like TLD-100 at high energy, the pellets showed an independent response. In contrast to TLD-100, the limestone pellets showed a higher response dependency for low-energy X-rays. During the fading study, the total TL intensity decreased by 20% within the initial 24 h of irradiation and then sustained stability for the subsequent week. The results of this study indicate that limestone pellets are effective as an X-ray dosimeter for doses between 1 and 10 Gy. • TL glow curve maxima observed at 120, 180, 250, and 330 °C. • As Opposed to TLD-100, a dose linearity observed between 1 and 10 Gy for X-rays. • CGCD of Limestone using general order kinetics with FOM equaling 2.37%. • Limestone pellets exhibited good TL emission and stabilized fading after a week. [ABSTRACT FROM AUTHOR]

The Material characterization and kinetic parameters based Thermoluminescence (TL) study of virgin and heat treated Pakistani Onyx marble is reported. Pellets of mineral under various heat treatments named as virgin (S1), pre-heated (S2), annealed (S3), heat-treated-slowly-cooled (S4), are prepared. Material characterization is performed using TGA, XRD, SEM-EDX, and ICP-OES techniques. ICP & EDXs shows C, O, Ca as major elements and Al, Mn, Mg, Fe, Si as impurity content. Crystalline nature under heat treatment remains unaffected up to 773 K as indicated by the XRD analysis. TGA shows sample is CaCO 3 with no mass loss from 303 to 893 K. XRD and TGA analysis concludes that TL analysis is possible within 303–673 K. After 03 Gy of β-irradiaton dose, the TL responses are investigated. All samples show a thermally stable peak around 552 ± 3 K. The kinetic features responsible for TL response are studied using Initial rise (IR) method, Chen Peak Shapes (CPS) analysis and P.N. Keating technique. Kinetic order values vary within 1.75–1.05. The activation energy ranges from 0.88 to 1.33 eV, frequency factor appears within 106-1010 s−1. Calculated parameters are validated by comparing MATLAB generated synthetic curves with experimental results. CPS and IR based synthetic curves are in good agreement with the experimental curves. Heat treated Sample S4 shows enhanced TL response as compared to other samples. [Display omitted] • Material characterization and TL kinetic parameters analysis of Pakistani Onyx. • Various heat treatments are used to observe Thermoluminesce response. • Thermally stable TL peak appears around at 552 ± 3 K for all sample groups. • IR, Chen peak shapes and P.N. Keating methods used to evaluate TL glow curves. • Curves are generated using GOK equation in Matlab to verify kinetic parameters. [ABSTRACT FROM AUTHOR]