Speaker
Stefan Gundacker
(Vienna University of Technology (AT))
Description
Silicon photomultipliers (SiPM) have a wide range of applications in high energy and medical detector physics. Their excellent timing properties and compactness make them particularly interesting for time of flight positron emission tomography (TOF-PET). This study aims at determining the optimum detector conditions for highest time resolution in a TOF-PET system. The measurements are based on the time over threshold method in a coincidence setup using the ultra-fast amplifier-discriminator NINO and a fast oscilloscope. We compare commercial SiPMs of different SPAD types (Hamamatsu MPPC S10931-025P, S10931-050P and S10931-100P) and production batches. Similar to crystal dimensions typically used in current PET facilities, we chose LYSO:Ce crystals of 2x2x10mm3 size and obtained, with SiPMs of 50x50μm2 SPAD size, a coincidence time resolution (CTR) of 175±6ps FWHM. To further explore the timing capabilities of the SiPM, we also coupled shorter, i.e. 2x2x5mm3, Ca-co-doped LSO:Ce crystals to the 50μm type and obtained 142±9ps FWHM CTR. This performance makes SiPMs ideal candidates for photodetectors in high resolution TOF-PET systems. The results will be discussed in terms of SiPM dark noise, photon detection efficiency (PDE) and photon yield.
Author
Stefan Gundacker
(Vienna University of Technology (AT))
Co-authors
Benjamin Armand Frisch
(CERN)
Etiennette Auffray Hillemanns
(CERN)
Hartmut Hillemanns
(CERN)
Paul Lecoq
(CERN)
Pierre Jarron
(Universita e INFN (IT))
Tom Meyer
(Conseil Europeen Recherche Nucl. (CERN))
