Raman and near-IR study on proton irradiated CR-39 detector and the effect of air-leak on damage formation

Raman and near-IR spectral studies have been made on the proton irradiated CR-39 plastics with 3.4 MeV at fluences ranging from 10¹⁰ to 10¹⁴ ionscm⁻². The density of –CH₂– group began to decrease after the air leak subsequent to the irradiation. This implies an important role of the oxygen on forming the permanent damage along the latent track. Production of OH group and some types of radicals was confirmed by near-IR observations in the air.