This paper describes the, LSO/LuYAP phoswich detector head developed for the ClearPET small animal PET scanner demonstrator that is under construction in Lausanne within the Crystal Clear Collaboration. The detector head consist's of a dual layer of 8 x 8 LSO and LuYAP crystal arrays coupled to a multi-anode photomultiplier tube (Hamamatsu R7600-M64). Equalistion of the LSO/LuYAP light collection is obtained through partial attenuation of the LSO scintillation light using a thin aluminum deposit of 20-35 nm on LSO and appropriate temperature regulation of the phoswich head between 30 degrees C to 60 degrees C. At 511 keV, typical FWHM energy resolutions of the pixels of a phoswich head amounts to (28 +/- 2)% for LSO and (25 +/- 2)% for LuYAP. The LSO versus LuYAP crystal identification efficiency is better than 98%. Six detector modules have been mounted on a rotating gantry. Axial and tangential spatial resolutions were measured up to 4 cm from the scanner axis and compared to Monte Carlo simulations using GATE. FWHM spatial resolution ranges from 1.3 mm on axis to 2.6 mm at 4 cm from the axis.
Transaction on Nuclear Science, Vol 53, n° 1 (2006) 25-29
- positron emission tomography
- phoswich detector
- small animal PET scanner