Evaluation of Organometallic Compounds for Gamma Detection in Plastic Scintillators

A series of copolymer of vinyl toluene containing various organometallic compounds have recently been synthesized. By taking advantage of the weak fluorescent characteristics of the organometallic compounds and the better understanding of the energy transfer and quenching process (J. Phys. Chem. 68:300 (1964)), it is possible to prepare organometallic scintillation plastics that may be useful for gamma detection. A 20% triphenyltinstyrene and vinyl toluene copolymer containing 3% PBD and 0.05% POPOP have now been evaluated at the Health and Safety Laboratory, New York Operation Office. The sample size was only 1 ⅝" by 1" thick cylinder. In general, the pulse height is 45-50% of that observed from anthracene, and the cross section is still less than that observed for sodium iodide. However, the photopeaks are definitely resolvable when evaluated for Mercury-203, Cadmium-109, and Cesium-137. In the last case, the energy resolution for 662 MeV photons lies between 16-19%.