High-energy-resolution scintillator: Ce3+ activated LaBr3

The scintillation properties of LaBr3 doped with 0.5% Ce3+ are presented. Under optical and gamma ray excitation, Ce3+ emission is observed to peak at 356 and 387 nm. The scintillation light output is 61 000±5000 photons/MeV at 662 keV. More than 90% is emitted with a decay time of 35 ns. An energy resolution (full width at half maximum over the peak position) of 2.85%±0.05% was observed for the 662 keV full absorption peak. A time resolution of 385 ps was obtained using BaF2 as second scintillator and gamma rays of Co60.