Scintillation Properties of Praseodymium Doped LuAG Scintillator Compared to Cerium Doped LuAG, LSO and LaBr3

Properties of praseodymium and cerium doped Lutetium Aluminum Garnet (LuAG) were compared with cerium doped Lutetium Oxyorthosilicate (LSO) and Lanthanum Bromide (LaBr3). Light yield, its non-proportionality relative to 662 keV γ-rays and the dependence of the energy resolution on energy of the detected γ-rays were measured. LuAG:Pr turned out to have good proportionality, with deviation from unity around 10% at 16.6 keV and 3% at 59.5 keV. This, together with relatively high light yield of 5600 phe/MeV results in a very good energy resolution of LuAG:Pr of 5.1% measured with 662 keV γ-rays. Coincidence time resolution was measured to be 308 ps, significantly larger than that of LSO:Ce - 166 ps. This can be explained by smaller light yield of LuAG:Pr and the fact that only around 25% of its scintillation is emitted in short decay time modes of 17.6 ns and 52 ns, while the rest is decaying with long time modes of 1.4 μs and 9 μs.