Performance studies of YAP:Ce crystal pillars for imaging application in Nuclear Medicine.

In order to design an Imaging system fpr Nuclaer Medicine with sub-millimeter spatial resolution we investigated the intrinsic image capability of a number of YAP:Ce crystal arrays. YAP:Ce is now available asneedle which are assembled into an array up 10 x 10 cm2. The cross section of needle is small (up tp 0.3 x 0.3 mm2) and its maximum height (30 mm) useful to detect 511 keV photons. YAP:Ce multi-crystal array matches vwey well PSPMT characteristics (Hamamatsu R2486) allowing to carry out sub-millimeter spatial resolution values. In this work several crystal array with needle cross section between 1 mm x mm ans 0.3 mm x 0.3 mm were taken into account. The height of crystals ranges between 1 mm and 28 mm. The crysrtals were irradiated by a Tc-99m source. The spatial resolution value ranges between 0.5 mm and 1.2 mm of FWHM and Detector Response Function FWHM between 7 mm and 10 mm. Position non linearity resulted close within ±200 µm.