Thermoluminescent response of MgO:Sm,Tb exposed to short wavelength UV radiation

UV radiation is a type of electromagnetic radiation, which is usually divided in parts according its wavelength: long-wave UV-A (400–320 nm), UV-B (320–280 nm), and shortwave UV-C (280–100 nm). The main source of UV radiation is the sun, but there are many man made artificial UV source, because it has different applications in several areas of the science and technology. Due to the UV radiation energy is in the order of magnitude bond energy of organic molecules it also has tremendous effects on human skin, and then, dosimetric methods to quantify the dose radiation are necessary. This work presents a study of the thermoluminescence response of MgO:Sm,Tb (0.4, 0.1 mol %) for different exposition times using a UV radiation lamp of 254 nm. MgO:Sm,Tb sample was synthesized by the solution combustion method and the obtained powder was manufactured in the pellet form, which were sintered at 1173 K. Before irradiation, the pellets were subjected to annealing treatment at 623 K for 30 minutes to eliminate any spurious Tl signal. The readouts were taken 5 min after irradiation using a Harshaw Model 4000 Tl reader. Results showed that UV radiation induced a Tl glow curve with one peak around 462 K, which intensity increases with the exposition time following a grown rate of the logarithmic type and reached a saturation for an exposition time greater than 40 min. It was also observed a low fading during the first 60 min after irradiation. These results are promising to development new thermoluminescent materials for dosimetric application of UV radiation. (author)