Investigation of Thermoluminescence Properties of Calcite from Kaman, Kırşehir

This study investigates the thermoluminescence (TL) properties and dosimetric performance of calcite samples, with particular emphasis on dose response, heating rate (HR) effects, and reusability (RU). TL measurements were carried out using a Lexsyg Smart TL/OSL reader equipped with a ⁹⁰Sr/⁹⁰Y beta source. The dose-response relationship was analyzed by irradiating the sample with beta doses ranging from 0.1 to 500 Gy, revealed a progressive increase in TL intensity. The TL glow curve exhibited two broad peaks at 100-116 °C and 238 °C, with a shift in the first peak temperature at higher doses. A fitting procedure was applied to analyze the dose-response characteristics of the material, revealing distinct b values for different dose ranges. The effect of HR on the glow curve was also studied, showing an anomalous increase in TL intensity with rising HRs, contrary to expectations from the standard theoretical model. Additionally, the RU of the material was assessed by performing 10 consecutive TL measurements after a 50 Gy irradiation, demonstrating minimal degradation in TL intensity, with low deviations from the mean and first values. This remarkable RU is crucial for ensuring the material's effectiveness in long-term dosimetric applications.