Simulation of ALTEA calibration data with PHITS, FLUKA and GEANT4

Abstract

The ALTEA-Space detector has been calibrated by testing its response to several monochromatic beams. These measurements provided energy-deposition spectra in silicon of 100, 600 and 1000 MeV/nucleon C-12 and 200 and 600 MeV/nucleon Ti-48. The results have been compared to three Monte Carlo transport codes, namely PHITS, GEANT4 and FLUKA. Median, full width at half maximum (FWHM) and interquartile range (IQR) have been calculated for all datasets to characterize location, width and asymmetry of the energy-deposition spectra. Particular attention has been devoted to the influence of δ rays on the shape of the energy-deposition spectrum, both with the help of analytical calculations and Monte Carlo simulations. The two approaches proved that, in this range of projectile charge, projectile energy and detector size, the leakage of secondary electrons might introduce a difference between the energy-loss and energy-deposition spectrum, in particular by changing the location, width and symmetry of the distribution. The overall agreement between the Monte Carlo predictions and the measurements is fair and makes PHITS, FLUKA and GEANT4 all possible candidates for simulating ALTEA-Space experiment.