Preliminary study for pixel identification on a modular gamma camera

Our grouphasrecentlyinvestigatedandproducednewscintigraphicprototypesbasedonadvanced scintillation structure.Theaimofthisstudyistodemonstratetheuseofscintillationmatriceswithsize equaltotheoverallareaofthePositionSensitivePhotomultiplierTube(PSPMT),todesignamodular gamma cameraandstudythesolutionofthedeadareaproblemsoptimizingtheoverallpixel identification. In thispaperweinvestigatetheresponseofdifferentcombinationswithcrystalsintegratedwithin tungsten structure,coupledwithH8500,R8900-C12andR11265-M64HamamatsuPSPMTs.Several scintillation matrices,whosedimensionsmatchtothephysicalareaofthePSPMT,havebeenanalysedso that wehavealsostudiedlimitsofdetectionfortheelementsofthematrixinthecriticalzonesofthe PSPMT,i.e.cornersandborders. In ordertoenhancethedetectabilityofscintillationelementsweimprovedthelightcollectionby depositing metalliclayersortreatingthetungstenstructurewithdifferentcoatingmaterials,andshaping the externalelementsofthescintillationmatrices. The resultshaveshowngoodenergyresolutionandtheproposedmethodcanbeappliedinmedical imaging forobtaininghighefficiency scintillationdevices.