Optimization of a lead-tungstate crystal/photodetector system for high-energy physics

The characteristics of a crystal/photodetector system with long size lead-tungstate scintillator PbWO/sub 4/ (PWO) were studied. The influence of different measurement conditions on the light yield and light yield homogeneity was investigated for electromagnetic calorimeter modules with projective geometry. We have tested different kinds of reflective materials for the crystal covering such as MYLAR (mirror reflection) and MILLIPORE, TEFLON, TYVEK (diffuse reflection), using different shapes of crystals (as a parallelepiped, as a truncated pyramid, as double truncated pyramid), using light guides and/or reflecting covering at the bottom of crystal. In our investigation we have used a photomultiplier tube.<
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