  CREME96 and GEANT4 are two well known particle transport codes through matter
in space science. We present a comparison between the proton fluxes outgoing
from an aluminium target, obtained by using both tools. The primary proton flux
is obtained by CREME96 only, covering an energy range from MeV to hundreds GeV
with the same result in both cases. We studied different thickness targets and
two different GEANT4 physics lists in order to show how the spectra of the
outgoing proton fluxes are modified. Our findings show consistent agreement of
simulation data by each tool, with regards both GEANT4 physics lists and every
thickness target analysed.
