Abstract
Today, estimating ionizing radiation doses through simulations using Monte Carlo codes is essential in many fields, particularly space radiobiology. Simulations are engaging because they are risk-free and significantly more cost-effective than experimental methods. Consequently, various codes have been developed to transport a broad spectrum of charged and uncharged particles across an extensive energy range from several keV to hundreds of TeV and beyond. These codes have diverse physical models, enabling users to select the most appropriate one for their simulations. Assessing the differences between these models is crucial for accurately estimating radiation doses. In this study, three different physical models from GEANT4 11.1.3 (FTFP_BERT, FTFP_INCLXX, and FTF_BIC) and the physical model of FLUKA 4–4.0 were evaluated to determine the depth dose distribution of protons (0.1 GeV–10 GeV) within the Snyder head phantom. The findings reveal that varying physical models yield different dose values. The paper thoroughly investigates the relative differences in the results obtained from FLUKA and GEANT4, expressed as percentages.