The effect of PPO concentration on the scintillation properties of a polystyrene based plastic scintillator

Plastic scintillator detectors are widely used in industry, medicine, nuclear research, and fundamental particle research. Numerous studies worldwide aim to gain better insight into and optimize this detector. In this study, polystyrene-based plastic scintillators were fabricated through thermal polymerization without initiator and with different wt% of PPO (2, 5, 10, 15, and 30 wt%) to examine the effect of PPO on scintillation properties and pulse shape discrimination. The features of these scintillators were compared and investigated. The results showed an optimal light yield at 15 wt% PPO. However, the neutron-gamma discrimination was directly related to the PPO concentration, so that for 30 wt% PPO, FOM and peak-to-valley ratio were 1.57 and 4.6 respectively. The aging test of plastic scintillators has shown an inverse relationship between the concentration of PPO and their lifespan.