Simulation of large angle backscattering spectra of channeled protons in Geant4

In this work a new open source simulation model based on GEANT4 toolkit is presented that allows the simulation of large angle elastic backscattering spectra of protons in single virgin crystals. The simulation model evaluates the backscattering yield based on the differential cross-section, modified by the close encounter probability with lattice atoms at a specific projectile position. Simulations were performed for 1-2.5 MeV energy protons channeled along the silicon, diamond, silicon dioxide and silicon carbide crystals. The comparison between experimental and simulated curves has shown that the developed model is capable of accurately simulating the channeling backscattering spectra of protons when angular beam spread is considered in the simulations. Although perfect match of the simulated spectra to the experimental ones was not achieved in all cases, the agreement between results is highly promising. The presented model is a proof of concept and further development of the model for the simulation of lattices with defects is underway.