PROPERTIES OF THE YAP-CE SCINTILLATOR

Light yield, light pulse shape due to gamma-rays and alpha-particles, energy and time resolutions for a 10 x 10 x 5 mm(3) YAP crystal couple d to the XP2020Q photomultiplier were studied. The measured light outp ut of 17 000 +/- 850 photons/MeV includes a correction for the calibra ted quantum efficiency of the XP2020Q. The fast component of the light pulse with the decay time constant of 26.7 +/- 0.12 ns also shows a f inite rise time described approximately by the time constant of 380 +/ - 45 ps. The YAP crystal which was studied exhibited an energy resolut ion of 5.7% for 662 keV gamma-rays from a Cs-137 source. This very goo d energy resolution is due to a low intrinsic energy resolution of 3.4 %. These characteristics, together with a good time resolution for Co- 60 gamma-rays of 160 ps measured at the threshold of 1 MeV, suggest a broad range of applications for the YAP scintillator. (C) 1998 Elsevie r Science B.V. All rights reserved.