Evaluation of Ce:SrAl2O4 crystalline scintillators

In this study, Ce-doped SrAl2O4 (Ce:SrAl2O4) crystals were prepared by a floating zone (FZ) method and experimental evaluations were performed for scintillator applications. In photoluminescence (PL) with an excitation around 320 nm, an intense broad emission peak appears around 380 nm due to the 5d-4f transitions. The PL decay time constants are approximately 30 ns. The X-ray induced scintillation spectrum also shows an intense broad emission peak around 380 nm. Among the samples evaluated with different concentrations of Ce, the absolute light yield under 137Cs is considerably high (∼3900 ph/MeV) when the concentration of Ce is 1.0%. In thermally stimulated luminescence (TSL) after X-ray irradiation, strong TSL glow peaks are observed at 110, 210 and 330 °C. The samples also shows optically stimulated luminescence (OSL) after X-ray irradiation, in which the emission appears around 380 nm due to the 5d-4f emission bands of Ce3+ while the samples is exposed to the stimulation light at 655 nm.