Comparative studies of YAG(Ce) and CsI(Tl) scintillators

The performances of YAG(Ce) and CsI(Tl) scintillators have been compared using photomultiplier tube (PMT) readout for γ rays and α particles. It is found that the energy resolution of YAG(Ce) is inferior to that of CsI(Tl). With Philips XP2971 PMT, we have obtained improved energy and time resolution for YAG(Ce), compared to the same, obtained by earlier workers using XP2020/Q. The best values of energy resolution (FWHM), obtained in the present work, for 662 keV γ ray, are 6% and 7%, respectively, for CsI(Tl) and YAG(Ce), whereas for 5.48 MeV α particles, the observed values are 6% and 8.4%, respectively. The pulse height response of both the scintillators has been found to be reasonably linear up to 1.3 MeV γ energy. A prompt time resolution of 1.3 ns (FWHM) has been obtained with a BaF2 – YAG(Ce) combination against 511–511 keV photopeak selection, which compares well with that obtained for a BaF2–CsI(Tl) combination, used by us.