Progress in the development of LuAlO3-based scintillators

LuAP:Ce and mixed LuYAP:Ce crystals are the promoted scintillation material s for positron emission tomography. These scintillators are presently being studied in three directions: 1) growth of large crystals with stable prope rties; 2) establishment of relationships between the composition of LuYAP:C e crystals and the scintillation properties; and 3) scintillation mechanism s in lutetium compounds. We performed the first bunch of 16 LuYAP:Ce crystals with size for the dete ctor module (2 x 2 x 10 mm(3)). The crystals show good correlation among gr owth parameters, light yield, and transmission spectra. To clarify the scin tillation mechanism in LuAP:Ce and LuYAP:Ce crystals, measurements of absor ption, emission, and excitation spectra of thermoluminescence and scintilla tion decay curves have been performed.