Performance of cerium-doped Gd 3 Al 2 Ga 3 O 12 (GAGG:Ce) scintillator in gamma-ray spectrometry

Performance of cerium-doped Gd3Al2Ga3O12 (GAGG:Ce) scintillator in gamma-ray spectrometry has been investigated. The measurements of two samples of GAGG:Ce cover the tests of emission spectra (maximum of emission at about 530nm), light output, non-proportionality, energy resolution, time resolution and decay time of light pulses. We compare the results with commonly known scintillators, such as NaI(Tl), LSO, LuAG etc. The results show that GAGG:Ce has a high light yield of about 33000ph/MeV as measured with Hamamatsu S3590–18 Si PiN photodiode [1]. The total energy resolution for 662keV gamma-rays from 137Cs source is equal to about 6%, whereas intrinsic resolution is equal to 5.2%. Additionally, we made basic measurements of photoelectron yield, non-proportionality and total energy resolution of small sample (5×5×5mm3) of GAGG:Ce crystal coupled to Hamamatsu MPPC array (6×6mm2). The results show that the performance of GAGG:Ce measured with the MPPC array are similar to those measured with the PMT.