The polystyrene based scintillator SCSN38, pure polystyrene and pure polymethyl-methacrylate have been irradiated with a beam of fast neutrons and with reactor neutrons. The radiation induced permanent optical absorption coeecients after total annealing in air are compared with data for irradiations. The strong diierences might be due to the high LET of the recoil protons elastically scattered ...
