LUMINESCENCE PROPERTIES OF CE-ACTIVATED YAG OPTICAL CERAMIC SCINTILLATOR MATERIALS

Scintillation and luminescence characteristics of a highly dense trans parent YAG:Ce-ceramic are reported and compared to those of a single c rystal. When excited with gamma-rays both types of materials display t he same dominant approximate to 85 ns decay, but the ceramic also show s a new rapid component of approximate to 20 ns that is completely abs ent in the single crystal. The scintillation output from the ceramic r eaches about 50% of that from the single crystal, having been diminish ed by unusual loss processes caused by the deformed lattice at the gra in boundary interfaces. A phenomenological model involving distortion of the band structure is proposed to explain the results of kinetic me asurements.