Fabrication and characterization of new LiF:Eu³⁺ sintered phosphors exposed to beta particles

Pellet-shaped LiF:Eu3+ phosphors were synthesized by sintering. To improve their thermolumine-scence characteristics, different growth conditions were used. Thermal annealing at 750C during 5h under air atmosphere provided the samples with highest sensitivity. Characteristic glow curves exhibit an absolute maximum centered at 203C and another less intense peak between 250 and 300C. The first peak has a position very suitable for dosimetry applications. Beta-irradiated samples displayed a thermoluminescence response that increases as the radiation dose increased in the 0.16-42.0Gy range. A fast fading of20% occurs in the first 10s after irradiation, followed by a remarkable stability at room temperature. Computerized glow curve deconvolution of experimental data obtained applying the McKeever method to resolve the individual peaks revealed that the glow curves fit to nine individual peaks. Activation energies were computed by using the initial rise method.