The optimum angle-cut of collimator for the dense objects in high-energy proton radiography

The use of the minus identity lenses with the angle-cut collimator can achieve high contrast image in high-energy proton radiography. This article presents the principle of choosing the angle-cut aperture of the collimator for the different energies and objects. The numerical simulation using the Monte Carlo code Geant4 has been implemented to investigate the entire radiography for the French test object. The optimum angle-cut apertures of the collimators are also obtained for different energies.