Optical transmittance and pulse shape discrimination of polystyrene/poly(methyl methacrylate)-based plastic scintillators

Polymethyl methacrylate (PMMA) is an optically transparent thermoplastic with favorable processing conditions. In this study, a series of plastic scintillators are prepared via thermal polymerization, and the impact of PMMA content on their transparency and pulse shape discrimination (PSD) ability is investigated. The fabricated samples, comprising a polystyrene (PS)-PMMA matrix, 30.0 wt% 2,5-diphenyloxazole (PPO), and 0.2 wt% 9,10-diphenylanthracene (DPA), exhibit high transparency with transmissivity ranging from 70.0 to 90.0% (above 415.0 nm) and demonstrate excellent n/ \(\gamma\) $\gamma$ discrimination capability. Transparency increased with increasing PMMA content across the entire visible light spectrum. However, the PSD performance gradually deteriorated when the aromatic matrix was replaced with PMMA. The scintillator containing 20.0 wt% PMMA demonstrated the best stability concerning PSD properties and relative light yields.