Improving decoding tube performance for the UWPET time of flight detector modules

The UWPET (ultraviolet positron emission tomograph) (a modified SP-3000 time-of-flight system) utilizes detector modules with eight BaF ₂ crystals coupled to five photomultiplier tubes. Although previous changes have improved module performance, further tests have been conducted in an attempt to increase both the inner/outer crystal decoding efficiency and the long-term optical coupling stability. It has been verified that KE103 compound provides the same UV light transmission as the Viscascil 600000 normally used. KE103 is generally considered the more mechanically stable project. Attempts were made to improve the energy resolution and peak position by increasing the amount of light reaching the decoding tube through a light-sharing technique and by reducing electronic noise associated with the decoding tube. At this time it appears that the initial configuration, developed by PETT electronics, is the most effective