LET effects of neutron irradiated plastic scintillators

The induced optical absorptions of polymers polystyrene (PS), polymethylmethacrylate (PMMA) and polyvinyltoluene (PVT), irradiated by neutrons and in γ fields, were measured for equal doses. The polymers are the most important bases for the use as plastic scintillators. The permanent damage in PS and PVT after recovery in air is larger for neutron than for γ irradiation. Electron spin resonance measurements (PS, PMMA) of involved radicals gave insight into radical kinetics during the recovery process. Correlations between radicals and optical absorption bands were found.