Simulation of parallel muons transmission imaging using Monte Carlo method

The Monte Carlo method-based Geant4 program is used to simulate the parallel muons (which are perpendicular to the ideal detectors) injecting into the French Test Object (FTO) model. Six ideal detectors, three over the model and three under it, are used to output the positions of muons, with which the incident and scattered muons tracks can be determined. Different transmission images of the FTO model can be obtained through calculating the transmission ratio before and after the model with three methods. The resolution of the first method and the second method is 2 mm2 mm, while the resolution of the third method is 1 mm1 mm and the edge of Cu and W can be distinguished obviously. Even the air sphere in the center of the FTO model can be observed visibly. Through all the three methods, the boundaries of the FTO model and the air outside it are very clear. The simulation results of transmission imaging indicate that the methods of parallel incident muons is feasible and practicable.