3D photon impact determination in monolithic crystals based on autocorrelation filters and RTP methods

• DOI: 10.1186/2197-7364-2-s1-a5
• Publication Date: 2015-06-18T07:35:53Z
• Authors: Pablo Conde; Antonio Gonzalez; Marco Bettiol; Andrea Fabbri; Roberto Pani; José María Benllo...; Albert Talens Agu...; Liczandro Hernandez; Filomeno Sanchez
• Keywords: Lyso-; Silicon Photomultiplier; Collimated light

In PET detectors based on monolithic scintillators, the photon impact position can be estimated from light intensity distribution (LD) photodetector pixels. Typically, there is a poor estimation of interaction positions towards edges when linear algorithms such as Center Gravity (CoG) are used. We present novel method to determine coordinates in thick crystals filtering digitized LDs each gamma-event by means an autocorrelation filter and raise power (RTP) positioning algorithm reduce border effects. The experimental setup was two detector blocks LYSO scintillator (50x50x20 mm3). Each crystal coupled SiPMs array 12x12 photosensors electronic readout that outputs information SiPM row column. Between blocks, collimated 9x9 22Na sources, separated 5 mm other, placed. optimum use RTP determined using third order intercept point (IP3) plots measured versus known positions. After applying fifth data, we found improvement spatial resolution 2.5 CoG used, 1.2 center region. this work show how accurately resolve 3D filters merged with methods. new approach it possible impacts close entrance 20 scintillators. reached at any depth comparable state-of-the-art approaches advantage proposed also provide continuous information.