Perspectives for high resolution and high light output LuAP:Ce crystals

After its introduction in 1994, LuAlO/sub 3/:Ce (LuAP:Ce) encountered problems of 1) low light output, 2) self-absorption of scintillation light, 3) nonproportionality of light output versus energy, and 4) poor energy resolution, and 5) small non-uniform crystals. Studying newly available LuAP:Ce-doped and undoped crystals (from Photonic Materials), we have found that self-absorption is chiefly dependent on the host crystal structure and not on Ce doping. We examined the scintillation properties of these crystals and found 6.8/spl plusmn/0.3% energy resolution for 662 keV for 2 mm/spl times/2 mm /spl times/10 mm pixels. The intrinsic resolution is equal to 2.8/spl plusmn/0.4% at 2360/spl plusmn/120phe/MeV (9800/spl plusmn/500 ph/MeV) light yield. These crystals have nonproportionality of 93/spl plusmn/4% at 16 keV and intrinsic energy resolution close to that of YAP:Ce. Fast components of the scintillation comprise only about half of the light that is emitted in 100 microseconds.