Scintillation properties of Lu₃Al_5-xSc_xO₁₂ crystals

The scintillation properties of Lu₃Al_5-xSc_xO₁₂ single garnet crystals doped with different concentrations of Sc³⁺ were investigated. The best scintillation properties were obtained for the crystal with x=0.2 in the melt. This crystal has a broad (FWHM approximately 1 eV) ultraviolet emission band with a maximum at 275 nm. An energy resolution of 7% is observed for the 662 keV photopeak. The main decay component of the scintillation pulse has an exponential decay time of about 600 ns and accounts for 90% of the total light yield. The total scintillation light yield was found to be about 22500 photons/MeV. Within 10% a linear response was obtained in the energy interval from 8 keV to 1.3 MeV. The energy resolution was found to be approximately inversely proportional to the square root of the excitation energy.