A SiPM-based TOF-PET detector with high speed digital DRS4 readout

We have developed γ-ray detectors with good time resolution, to supplement positron emission tomography (PET) with time of flight (TOF) for better localization of the positron annihilation. This will improve the quality of medical images and reduce exposure times. We report results of LYSO scintillating crystals (3×3×15 mm3) irradiated with a 22Na source and coupled to silicon photomultipliers (SiPMs) readout with a waveform digitizer. Improved time resolution, 188 ps FWHM, was obtained with the signal trimmed by a clipping capacitance.