Revisited position arithmetics for LaBr3:Ce continuous crystals

The development of the molecular imaging technique based on radiopharmaceuticals requiring sophisticated devices with sub-millimeter spatial resolution and high detection e±ciency. Recently, in the field of scintillation gamma camera, it has been demostrated continuous crystals may improve spatial resolution with respect to the use of scintillation arrays. In this work we propose a new algorithm that improve spatial resolution. It calculates the position from a single scintillation event by squaring the charge collected on a multi-anodes photomultiplier tube (MA-PMT). It is able to remove the position linearity distortion due to the light reflections and the truncations at the crystal edge. We present measurements from a compact gamma camera based on a sample of 51 mm x 51 mm x 4.0 mm LaBr3:Ce continuous scintillation crystal, coupled to a MA-PMT Hamamatsu H8500. The results show a strong improvement in spatial resolution and confirm the high potential in using of LaBr continuous crystal for molecular imaging applications.