A simple method for measuring the performance of plastic scintillating materials

The authors propose a method to measure the relative efficiency of scintillating materials based on the fabrication of thin films (10 to 100 μm) with at least one of the faces roughened. Excitation with a monochromatic beam of ultraviolet light then permits a thorough study of the energy transfer in plastic scintillators and their spectral emission and a comparison of their intrinsic scintillation intensity. The results obtained are reproducible and in satisfactory agreement with direct measurements with α radiation. It is shown that the standard ternary scintillator PS+1%butylPBD+dimethylPOPOP cannot be used for the core of a plastic scintillating fiber (PSF) with a diameter smaller then 0.4 mm. Instead, a binary solution, PS+0.6%PBBO, has been studied which makes it possible to consider the production of PSF with a diameter less than 50 μm, with acceptable crosstalk and good efficiency