PROPERTIES OF THE YAG-CE SCINTILLATOR

Light yield, light pulse shape due to gamma-rays and alpha-particles, energy resolution and time resolution of the new YAG:Ce scintillator were studied using a light readout by means of the XP2020Q photomultiplier and the S3590-03 photodiode. The light yield of 20 300 +/- 2000. photons/MeV was determined using three independent methods. The light pulse produced by gamma-rays consists of two components with the decay time constants of 87.9 ns and 302 ns respectively. The light pulse measured for alpha-particles exhibits a faster and less intense fast component with the decay time constant of 68.4 ns. The energy resolution obtained was 11.1% and 11.7% for the 662 keV gamma-rays from a Cs-137 source as measured with the photomultiplier and the photodiode readout, respectively. A time resolution of 1.3 ns was observed for Co-60 gamma-rays (at 100 keV threshold) with the crystal coupled to the XP2020Q photomultiplier. The YAG: Ce scintillator with the peak emission at 550 nm is a good candidate to replace CsI(Tl) and BGO scintillators in detection of light charged particles when photodiode readout is of importance. The observed difference in the light pulse shape due to gamma-rays and alpha-particles suggests good performance of the crystal in the pulse shape discrimination method for the particle identification.