Determination of thermoluminescence properties of the Bursa meteorite

In this thesis, the structural and characteristic Thermoluminescence (TL) properties of the Bursa meteorite were examined, and the TL kinetic parameters of the meteorite were determined. In this context, the dosimetric potential of the meteorite was investigated using induced TL (ITL), while natural TL (NTL) analyses were used to estimate the perihelion distance and cosmic radiation exposure age (CRE). SEM–EDS analyses showed that the morphological features and chemical elemental compositions of the meteorite are consistent with ordinary chondrites. XRD results confirmed that the dominant mineral phases consist of silicate minerals, and the TL signal was evaluated to originate from the defect structures of these silicate minerals. TL measurements were performed on a sample annealed at 500 °C for 15 minutes using a 565 nm filter combination. The dose–response experiment revealed that TL intensity increased linearly for doses applied in the 0.5–50 Gy range. In reusability tests, a decrease of approximately 3.5% was observed for 20 Gy, while a 5% increase was recorded for 50 Gy. These results demonstrate that the Bursa meteorite exhibits stable behavior under repeated use. Experiments conducted at increasing heating rates (1–5 °C/s) resulted in higher peak maximum temperatures, lower peak intensities, broader full widths at half maximum (FWHM), and reduced total areas under the glow curves. The activation energies of the traps contributing to the TL signal were calculated using the initial rise method and determined to arise from nine individual traps in the 0.90–1.70 eV range. The kinetic parameters of these nine traps were evaluated through computerized glow-curve deconvolution. In the fading experiment, a fading level of 30.83% was observed after a one-week waiting period; theoretical fading analysis showed that the fading predominantly originates from the first three shallow traps, indicating that the material is suitable for short-term dosimetric applications. Furthermore, analysis of the NTL glow curve yielded a perihelion distance of approximately 1.007 AU and a lower limit of 11,000 years for the CRE age of the meteorite. These results provide important insights into both the TL properties and the astrophysical history of the Bursa meteorite. Keywords: Meteorite, thermoluminescence, dosimetry