New characterization and evaluation of BaSO4: Eu as a thermoluminescent radiation dosimeter

Thermoluminescence (TL) dosimetry is used in radiation protection and for measuring absorbed dose to patients in diagnostic radiology and radiotherapy. The main aim of the study herein was to assess the TL properties of BaSO4: Eu nanophosphors following irradiation with low dose & gamma;- and X-rays. BaSO4 phosphors activated with various concentrations of Eu were prepared by the co-precipitation method. The highest radiation sensitivity was obtained for an Eu concentration of 0.5 mol%. The TL properties in terms of glow curve, heating rate, reusability, fading and order of kinetics were studied. Optimized BaSO4: Eu irradiated with doses from 1.25 to 50 mGy displayed a major TL peak at & AP;220 degrees C and exhibited a linear response with absorbed dose. The reusability test was performed for ten consecutive irradiations, readings, and annealing cycles, and showed a slight decrease in TL after the first cycle after which it was stabilized. Signal fading measurements were performed for irradiated samples over 50 days, where a signal loss of about 0.14 % per day was observed.