Energy loss correction on multiple Coulomb scattering of muons simulated by Geant4

Abstract

The scattering angle distribution of muons passing through an object is crucial reference data for the application of the accelerator muon scattering imaging. In this study, the scattering angle distribution of muons in the accelerator energy region was simulated using the Monte Carlo toolkit Geant4 and calculated using the Molière’s theory. The results show that a significant deviation occurs when Molière’s theory is used to calculate the scattering angle distribution of muons in the accelerator energy region. We demonstrated that the deviation is due to the energy loss. Therefore, an energy loss correction was introduced on Molière’s theory, after which the calculated results are in good agreement with the Geant4 simulation. Furthermore, the relative error caused by using Moliere’s theory with different energy losses was calculated for muons of different energies, which can help clarify the importance of energy loss for accelerator muon scattering imaging.