SSPM Readout of LSO, (Lu-Y)AP:Ce and PWO-II Pixels for PET Detector Modules

We have studied the performance of recently developed solid state photomultipliers (SSPMs) with 2.1times2.1 mm² sensitive area as a readout for small LSO, (Lu-Y)AP:Ce and PWO-II scintillator crystals. The SSPM is based on the p⁺-p-n⁺ structure which was optimized for blue/UV light detection. It operates at a gain of >10⁵ and shows >25% photon detection efficiency in the 380-600 nm spectral range. Energy and timing spectra were measured using a ²²Na gamma source. Energy resolutions of 13%, 25% and 50% FWHM were measured for 511 keV gammas with the LSO, (Lu-Y)AP:Ce and PWO-II scintillator crystals respectively. A coincidence timing resolution of 710 ps (FWHM) was measured between two identical LSO+SSPM modules.