Energy transfer, fluorescence and scintillation processes in cerium doped RE3+Al2O3 fast scintillators

Modern applications of scintillators in medical imaging of human body (Positron Emission, Tomography-PET scanning, γ-Cameras and other X-ray tomographies) require improved or even quite new scintillators which should be characterized by (i) fast response, (ii) high density and (iii) high light yield. At present time new scintillating crystals are investigated, mainly those having perovskite lattice structure of the formula RE3+AlO3:Ce where RE3+=Y3+, Gd3+ and Lu3+. Here, we will present the newest data with summarizing properties of these types of scintillators including the mixed ones. Energy transfer processes between Ce3+ main centers and Ce3+ multisites are discussed together with their mechanisms including processes between Ce3+ and Gd3+ ions. Finally, the characteristic properties of scintillating crystals based on perovskite structure are reviewed. (author)