Thermoluminescence characteristics and kinetic analysis of beta irradiated Ca4LaO(BO3)3 phosphor

Abstract

Thermoluminescence (TL) properties of synthesized Ca4LaO(BO3)3 exposed to beta radiation were analyzed and TL kinetic parameters of activation energy E (eV), the frequency factor s (s-1), and order of kinetics b were determined in this study. TL glow curve recorded in 25–500 °C range presented two TL maxima around 70 and 200 °C and therefore, thermal cleaning was utilized for the further investigations on a single TL maximum. To investigate dosimetric characterizations of Ca4LaO(BO3)3, additive dose and various heating rates, reusability, and storage time measurements were performed. Ca4LaO(BO3)3 has a linear dose range between 10 to 100 Gy with a heating rate of 2 °C/s. An anomalous case of heating rate behavior was attained for the TL measurements carried out using variable heating rates between 0.1 and 10 °C/s which was considered through the semi-localized transition model. Reusability and storage time measurements indicated the results within the 5% standard deviation. The kinetic parameters were estimated by the initial rise (IR) and glow curve deconvolution (GCD) methods. Continuously distributed trapping levels were identified by TM–Tstop with E ranging from 1.25 to 1.45 eV. GCD identified that the glow curve expressed general order kinetics and consist of three overlapping traps.