MATSIM: A voxel model for the astronaut dosimetric phantom MATROSHKA

The AIT Austrian Institute of Technology coordinated the project MATSIM (MATROSHKA Simulation) in collaboration with the Vienna University of Technology and the German Aerospace Center, to perform FLUKA Monte Carlo simulations of the MATROSHKA numerical phantom for the radiation environment at the International Space Station (ISS). MATSIM, a voxel model of the MATROSHKA phantom was developed during the project MATSIM Phase-A. In this paper we describe results of the project Phase-B of MATSIM, Monte Carlo simulation of the absorbed dose and the neutron fluence assessed inside the whole model phantom. The simulations are verified by reference measurements using thermoluminescence dosimeters, an ionisation chamber and a tissue equivalent proportional counter (TEPC). Further investigations are carried out for ISS cosmic radiation conditions. MATSIM provides a comprehensive risk assessment of radiation hazard to humans working in space onboard the ISS, for missions to the Moon, Mars and beyond, as well as for terrestrial mixed radiation fields comprising ionizing high-energy particle radiation.