On the measurement of degradation and recovery of scintillating plastic fibres

Scintillating plastic fibres find an increasing number of applications in different fields ranging from elementary particle detection to radiobiology. One of the yet open questions is the long time stability of these fibres. For this sake, experiments have been performed under 2 MeV electron and under 70 MeV proton irradiation, in a way so that the counteracting effects of radiation-induced degradation and thermal defect annealing at room temperature are well separated in time scale. Thus, it became possible to determine them both, and, furthermore, to establish predictions for the fibre efficiency under any operational condition. The fibre degradation scales with the accumulated electronic energy density