Investigating the capability of plastic scintillation detectors in design of a muon radiography system by Geant4 code

Imaging and identifying materials with high atomic numbers and densities, especially radioactive materials, is one of the issues that have been especially considered in recent years. Due to some limitations in conventional and old imaging techniques, finding an alternative method is very important. The cosmic muons with an infinite source are one of the sources that have been recently studied for heavy objects imaging, and the major efforts in this field have focused on increasing the accuracy and efficiency of muon radiography systems. Use of plastic scintillator improves the accuracy and reduces the cost of muon radiography. In recent decades, different methods have been proposed for the use of these scintillators in development of muon radiography systems. Since the basis of the work of radiography systems is the spatial resolution of the detector, any study that can increase the accuracy of a muon detection system will ultimately improve the quality of muon radiography system. In this study, using a special configuration of plastic scintillators and photomultiplier tubes, the resolution of the muon location identification on the detector plate is optimized. The simulations performed by Geant4 code for different states, show that the final resolution of the detector plates is about 1 cm and, in terms of the resolution of detection, the best scintillator available for the proposed system is BC-408. In addition, among the examined photomultiplier tube layouts, the most accurate configuration is square alignment with uniform distances and the most suitable angle of positioning of the plates relative to the horizons is 10 degrees.