The Scintillation Process in Plastic Solid Solutions

Abstract

The scintillation process has been studied in a number of systems involving a solid solution of an organic fluor in polystyrene or polyvinyltoluene. It has been determined that direct excitation of the solute by the ionizing radiation contributes a negligible amount to the observed scintillation for the concentrations studied. Fluorescence of the solvent followed by radiative transfer to the solute is a significant process, but the major fraction of the scintillation, in the more efficient systems, is transferred from the solvent to the solute by a nonradiative process. Comparison of optical data with data of pulse size vs concentration points to dipole-dipole interaction as a means of energy transfer. Comparison of results with alpha and beta particles shows that the same degree of quenching is present in the solvent for both types of excitation.