Influence of Y-codoping on the PbWO4:MO luminescence and scintillator characteristics

We present measurements of radioluminescence, photoluminescence, thermoluminescence and decay kinetics (excitation by UV and Na-22 photons) on Mo- and (Mo, Y)-doped PbWO4 single crystals. A wide concentration range (200-50 000 ppm) of Mo-doping is considered. Comparing to Mo-doped PbWO4 crystals Y-codoping results in significant suppression of trapping states and improvement of temporal characteristics, consisting namely in acceleration of the scintillation decay process. Moreover, codoped crystals with an optimum Mo concentration (2750 - 10 000 ppm) show an increased light yield, while temporal characteristics are comparable to those of undoped PbWO4. (C) 2002 Elsevier Science B.V. All rights reserved.