Investigation on a small FoV gamma camera based on LaBr3:Ce continuous crystal

Recently scintillating crystals with high light yield coupled to photodetectors with high quantum efficiency have been opening a new way to make gamma cameras with superior performances based on continuous crystals. In this work we propose the analysis of a gamma camera based on a continuous LaBr3:Ce crystal coupled to a multi-anodes photomultiplier tube (MA-PMT). In particular we take into account four detector configurations, different in crystal thicknesses and assembling. We utilize a new position algorithm to reduce the position non linearity affecting intrinsic spatial resolution of small FoV gamma cameras when standard Anger algorithm is applied. The experimental data are obtained scanning the detectors with 0.4 mm collimated 99mTc source, at 1.5 mm step. An improvement in position linearity and spatial resolution of about a factor two is obtained with the new algorithm. The best values in terms of spatial resolution were 0.90 mm, 0.95 mm and 1.80 mm for integral assembled, 4.0 mm thick and 10 mm thick LaBr3:Ce crystal respectively.