Influence of doping on the emission and scintillation characteristics of PbWO4 single crystals

X-ray excited luminescence spectra, wavelength-resolved thermoluminescence glow curves, ultraviolet and Na-22 excited emission decays, and Co-60 excit ed light yield were measured on a set of high purity (99.9999%) PbWO4:X (X= Lu3+, Y3+, Gd3+, Sc3+, Nb5+, Pb2+) samples grown in an equivalent way. Posi tive influence of trivalent doping (Lu, Gd, Y) was noted, which consists in suppressing the deeper trapping states in the PbWO4 structure. Such states are related to the radiative recombination processes in the green and red part of the spectra. The presence of the green emission centers also result s in the increase of the slow recombination decay components in the microse cond time scale. High concentration of the dopant ions (670 atomic ppm for PbWO4:Nb) results in the creation of new nonradiative recombination sites, which suppress the recombination decay components and the light yield as we ll. (C) 2000 American Institute of Physics. [S0021- 8979(00)01809-0].