3D-Printed Plastic Scintillator: A Potential Avenue for Hetero-Structured Radiation Detectors

The concept of a heterostructure-based scintillation detector has been proposed as a potential alternative to current time-of-flight positron emission tomography (TOF-PET) detectors. In a heterostructure design, a dense scintillator (matrix) works in synergy with a fast-timing light scintillator (filler). The design often includes complex geometries, necessitating precise machining. The application of 3D printing technology can facilitate the fabrication of such complex geometries. This study presents the formulation and fabrication of a 3D-printed plastic scintillator, which has been identified as a potential filler material. The developed scintillator shows better rise and decay times compared to commercial plastic scintillators such as EJ-200. We have measured a coincidence time resolution (CTR) of 225 ps using $\gamma - \gamma $ coincidence. Monte-Carlo simulations were performed using the Geant4 toolkit to validate the advantages of using complex filler material designs. The simulation outcomes demonstrate significant improvement in the performance of heterostructures in the case of complex designs over simpler ones. The findings of this study underscore the promise of using 3D printing technology for producing complex heterostructures. This can help in advancing the development of TOF-PET detectors with comparatively reduced effort.