LEAD SULFATE SCINTILLATOR CRYSTAL-GROWTH FOR PET APPLICATIONS

It has recently been shown that lead sulfate (PbSO4) is a promising sc intillator material for use in PET detector systems. However, for lead sulfate scintillators to be useful in such an application, a techniqu e must be developed to grow large optical quality crystals of this mat erial. This paper describes our research into the high-temperature sol ution growth of PbSO4 crystals. We report on the systematic selection of solvent materials including KCl, LiCl, PbCl2, Na2SO4 and Li2SO4. Ou r studies indicate that Na2SO4 is the best solvent. With Na2SO4 as the flux, we obtained PbSO4 single crystals of several millimeters in siz e by Bridgman crystal growth method. We employed ACRT (Accelerated Cru cible Rotation Technique), to resolve the constitutional supercooling problem, thus increased the crystal yield and reduced the number of gr ains. Finally, we compared the scintillation properties of synthetic P bSO4 crystals we grew with previous measurements on natural anglesite and other synthetic crystals, and found them nearly identical.