Scintillation Properties of Praseodymium Activated ${\rm Lu}_{3}{\rm Al}_{5}{\rm O} _{12}$ Single Crystals

Scintillation properties of LuAG:Pr grown by Furukawa Co. Ltd., Japan, have been studied. The best crystals display light outputs up to 19000 ph/MeV and an energy resolution of 4.6% at 662 keV. The scintillation yield is found to be a function of size and temperature of the sample; it can be enhanced by 40% upon heating to 450 K. Radioluminescence spectra show both
d
-
f
and
f
-
f
transitions of Pr
³⁺
ions; the contribution of the latter increases with temperature. The scintillation decays are complex, with a fast decay constant of 20 ns. The presence of
¹⁷⁶
Lu induces high background activity.