Scintillation properties of transparent Lu₃Al₅O₁₂ (LuAG) ceramics doped with different concentrations of Pr³⁺

Transparent ceramics of Pr-doped (0.2 mol%, 0.6 mol%, 1 mol%, and 2 mol%) Lu₃Al₅O₁₂ (LuAG) scintillators produced by the sintering method are discussed. These materials were cut to the specimens with physical dimensions of 5 × 5 × 2 mm³. Similar size specimens were also prepared from Czochralski grown Pr:LuAG single crystals to compare scintillation properties. Their transmittance and radio luminescence spectra were evaluated. All specimens were highly transparent in wavelength range above 300 nm, and intense Pr³⁺ 5d-4f emission was detected around 310 and 370 nm under excitation with X-ray. Under ¹³⁷Cs γ-ray is irradiation, 2 keV photo-absorption peaks were also clearly observed in each sample. The Pr 0.6 mol% doped LuAG ceramics demonstrated highest light yield achievable among the ceramics, and it was half of that observed in the single crystals. Under pulse X-ray excitation, the decay time constants became faster when Pr concentration increased, and. the fastest decay (∼5.7 ns time constant) was noticed in the 2 mol% doped ceramic. (