Radiation damage studies on the optical and mechanical properties of plastic scintillators

This paper describes the radiation damage studies on a large volume plastic scintillator based in polystyrene doped with PPO and POPOP. The consequenc es on their mechanical and scintillation properties were evaluated before a nd after irradiation with different dose rates of Co-60 gamma radiation, in several doses, The optical results show a significant difference in the ra diation susceptibility, when the plastic scintillator is irradiated at low rate (0.1 kGy/h) with that irradiated at high dose rate (85 kGy/h). The los ses in the optical and mechanical properties increase as the irradiation do se is increased. The damage evaluated by the transmittance, emission intens ity, pulse height and tensile strength was normalized as a damage fraction and fitted by a bi-exponential function. It was observed that the damage fo r irradiation is not permanent and it obeys a bi-exponential function. (C) 1999 Elsevier Science B.V, All rights reserved.