Thermoluminescence behaviour of GdAlO₃:Yb³⁺ under gamma exposure

Thermoluminescence behaviour of Yb³⁺ doped GdAlO₃ was studied for solution combustion synthesised phosphor. The TL glow curve was recorded under gamma radiation. The Tl glow curve was recorded for various heating rate for constant 0.25 kGy gamma radiation to optimize the heating rate. The optimized heating rate was obtained at 4 °C s⁻¹. The effect of gamma dose on TL behaviour of the phosphor was studied by recording the TL for different gamma radiation dose from 0.25 to 1.25 kGy. For lower gamma dose the TL glow peak consists kinked peak with T_m at 397 and 432 K. As the gamma dose increases the T_m at lower temperature side vanished and the TL glow curve consists only one peak of higher temperature i.e. 432 K. To explain the variation in TL behaviour with variable gamma dose the TL glow curve for different gamma dose was analysed by using computerized glow curve deconvolution method. The kinetic parameters were calculated for all the deconvoluted peaks by using Chen’s peak shape method. Activation energy for higher temperature peak is more than lower temperature peak due to deeper and shallow traps respectively.