Fluence to dose equivalent conversion coefficients for ICRP110 voxel phantoms with aluminum and polyethylene shielding using GEANT4

Fluence-to-dose-equivalent conversion coefficients are essential for assessing astronaut radiation exposure in space. In this study, we calculate these coefficients for the ICRP110 male and female voxel phantoms under multiple shielding configurations: aluminum shells with mass thicknesses of 5, 10, 20, and 30 g/cm2, and a polyethylene shell with 30 g/cm2. Simulations are performed using the GEANT4 Monte Carlo toolkit for all ions from Z = 1 to 28 over a kinetic energy range of 1 MeV/n to 100 GeV/n. Dose equivalents are computed using both the ICRP60 and NASA quality factors. Organ-specific dose coefficients and their energy dependence are presented, providing reference data for spacecraft shielding design. At solar maximum, when the GCR flux is at its minimum, the effective dose equivalent is reduced by up to 31% and 18% using the ICRP60 and NASA quality factors, respectively, for the thickest shielding considered. Open Access This article is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License, which permits any non-commercial use, sharing, distribution and reproduction in any medium or format, as long as you give... [797 chars]