Gamma ray detection in PET application with fast scintillators coupled to avalanche photodiode

The use of Avalanche PhotoDiodes (APD) coupled to fast inorganic scintillators is evaluated for possible applications in medical systems. Several tests have been done on different configurations built coupling commercially available APD with scintillators like YAP and GSO. Experimental evaluation of performances like energy range, energy and time resolutions has been obtained. Starting from these results Monte Carlo simulations have been carried out to model a multi-element detector designed for possible PET applications. Some quality factors have been defined to compare the characteristics of the different single detectors tested. The Monte Carlo results are also used, in a feedback process, to optimize the use of the single element of the arrays.