Advancements in neutron dosimetry: A comprehensive FLUKA simulation of PLASTIC scintillator response across multiple irradiation geometries

Abstract

The present study offers a new computational tool for characterizing neutron particle spectrums and calculating dose, which may be helpful for use in medical imaging, nuclear physics, and industrial process applications. Using a state-of-the-art detector response matrix, this study explores the complex response behavior of a PLASTIC scintillator to neutron interactions. Scintillation detectors have unique interaction properties, and the investigation relies on this for a detailed analysis of their performance. FLUKA simulation code and the FLAIR interface are used to calculate the neutron energy deposited on the scintillator for a full range of neutron energies 0.001–10 MeV and three types of irradiation; Axial, non-axial, and Radial. This very extensive sim shows the subtleties of the response of the scintillator material for a slightly off-center hit, where the neighbor hits over time would affect the overall measurement depending on the orientation in which the scintillator is mounted and whether it can detect it. The results showcase the effectiveness of the detector in differentiating between different energies of neutrons and the decrease in energy resolution with respect to neutron energy, a key aspect of neutron detector design and applications. Additionally, the study showcases the breadth of applicability of Monte Carlo simulations to create a versatile detector response matrix and function to strengthen fundamental neutron interaction knowledge. This key piece of groundwork lays the foundation for future work on the behavior of other types of particles and enables new applications in accurate neutron detection and measurement.