Physics of Lead Tungstate Scintillators

A brief review of recent results, obtained during a systematic study of the luminescence and photo-thermally stimulated defects creation processes in various undoped and doped lead tungstate crystals, is presented. The origins of various emission bands are clarified. Several types of localized excitons are identified and their decay into electron and hole centers is found. The origin of the centers, created at the decay of the self-trapped and localized exciton states and the defect-related states, is studied both by the thermally stimulated luminescence (TSL) and the electron spin resonance (ESR) methods. The origin of the TSL peaks and the mechanisms of the defect creation and recombination processes are discussed.