Comparison of digital and analog silicon photomultiplier for positron emission tomography application

In recent years, silicon photomultipliers (SiPMs) became popular candidates for applications in positron emission tomography (PET) scanners or PET based multi-modality detectors. In this paper, we perform a comparative study of digital and analog SiPM in gamma spectroscopy with a lutetium-yttrium oxyorthosilicate (LYSO) scintillator. The energy spectrum in terms of photo-electron numbers (fired pixels) is obtained directly from the digital SiPM. The energy spectrum obtained with analog SiPM is converted to number of fired pixels using single photoelectron spectrum measurement. Non-linear behavior of both detectors is studied. Energy response for 511 keV gamma ray under non-linear conditions for both detectors are corrected using a Monte-Carlo simulation tool.