Investigation of luminescence mechanism in La0.2Y1.8O3 scintillator

La0.2Y1.8O3 is a new and promising scintillator which is based on the host material without doping. Here the time gated X-ray excited optical luminescence is measured by using the excitation energy below, above and at the La L3-edge. A relatively slow and broad emission with peak at 415 nm has been observed as the dominant emission. Also, a weak emission at 360 nm is observed at the fast window, associated with the recombination of trapped excitons in Y2O3 host. The observations show that the broad emission at 415 nm is most likely due to the recombination of trapped excitons associated with the La3+ doping into Y2O3 sites.