Physics:Radiation damage in plastic scintillators

Radiation damage is the general alteration of the operational and detection properties of a detector, due to high doses of irradiation. There are three main aspects of radiation stability in plastic scintillators used as detectors: polymer hardness (optical stability), dopant stability, and stability of the fibre waveguide structure. The major role in the scintillation light losses are due to the bulk effects in the polymer. Considerable permanent absorption remains in the polymer as a result of irradiation. Several excited species can also be produced. The light yield is reduced by about 20% for a dose of 10⁵ Gy. The transmittance loss is only about 2-6% at the same level (see Bross91). Damage to dopants is of much less importance.

In scintillating fibres, radiation produces degradation of the scintillating core, polymer cladding and core/cladding interface effects. For reference, also Marini85.