THE STUDY OF SMALL AND LARGE-SIZE LUALO3-CE3+

The LuAlO3:Ce3+ system was shown to be a promising scintillator for me dical imaging devices. Recently, efforts were focused on the improveme nt of its scintillating properties. Several large size crystals with v arious cerium concentrations were grown. Emission spectra, fluorescenc e decay times and light yields, both under gamma-ray and X-ray excitat ion, were measured under various experimental conditions. A reabsorpti on process is shown to take place in this material. This process is re sponsible for the observed decrease of the light yield when increasing the size of the sample.