TL response of Sm-doped MgO to 60Co gamma radiation

The thermoluminescent (TL) response of MgO doped with different rare earths was investigated. The TL material was synthesized by the solution combustion method and sintered at 1173 K; the obtained powders were prepared in pellet form. Before irradiation, the dosimeters were annealed at 623 K for 30 min to eliminate any TL signal generated during their manufacture. Independent tests were performed doping the MgO with Tm, Dy, Ce and Sm. The highest TL response was found for Sm-doped MgO (MgO:Sm) reaching the highest sensitivity for 0.4 mol% of Sm. For this sample, the TL response showed linearity from 0.001 to 500 Gy of 60Co gamma radiation. The lower detection limit was found to be equal to 1.17 mu Gy. The sensitivity of the MgO:Sm prepared dosimeter was approximately 10% the sensitivity of the commercial TLD-100. The TL signal fading was found to be 6% after one month. The deconvolution of the glow curve showed a symmetric peak with a general order kinetics, b, centered at 474 K. These results suggest that this new TL material could be a promising detector to use in diverse dosimetry applications.