Validation of Geant4 Physics Models Relevant for Space Radiation

Abstract

In order to use GEANT4 toolkit in the energies relevant to the space radiation it has been tested few of electromagnetic and hadronic models of it by comparing simulated values with NIST data and other experimental data available. For the validation of electromagnetic models energy-loss and electronic stopping powers are considered whereas for the validation of hadronic models, isotope production cross-sections and total fragmentation cross-sections are considered. The stopping power values simulated for protons in Al are agreeing very well with NIST database values. The energy-loss and residual energy values simulated for alpha particles in Si and Al respectively are in good agreement with experimental values at high energies and low-thicknesses of target materials. The stopping power values of alpha particles and Fe ions in Al are also agreeing well with tabulated values at the small thickness of target materials. The proton - proton production cross-section values for liquid hydrogen and polyethylene are within the limits of experimental errors. Although total fragmentation cross-sections for Fe ions in polyethylene and aluminum are not agreeing with the experimental values at low energies, they are agreeing at the peak of GCR spectrum which is around 1 GeV/nucleon. So the selected physics models used in the present simulation work can be used for the space radiation protection studies.