Characteristics of the new YAlO3 compared to BGO and GSO

The characteristics of a novel, fast scintillation material YAlO/sub 3/:Ce with high density (5.35 gm/cm/sup 3/) and high light yield were investigated and compared to those of other scintillation materials. The decay of the scintillation light could be described by the sum of two exponentials with decay constants of 31 ns and 246 ns, contributing 98% and 2% to the total light yield, respectively. A light yield of 19700 photons/MeV was measured by comparing the number of photoelectrons produced in YAlO and in BGO under the same conditions. The energy resolution at a gamma ray energy of 511 keV was 6.7% for a 4.0-mm*8.0-mm*25.0-mm sample. The full width at half maximum (FWHM) of a timing measurement using two YAlO crystals detecting annihilation quanta (with 200-keV threshold) was 1.1 ns. Monte Carlo simulations showed that the crystal depth for the absorption of 90% of 511-keV gamma quanta is 51.8 mm in YAlO (compared to 25.2 mm in BGO).<>