MATSIM Phase-B - Verification of the Numerical MATROSHKA Model and Monte Carlo Simulations in the ISS Radiation Environment

The aim of MATSIM Phase-B is the validation of the numerical simulation model of MATROSHKA for photon and neutron reference radiation fields, which are available in Austria. The project MATSIM is a co-investigation of the ESA ELIPS-project MATROSHKA, a world wide collaboration that comprises 21 research institutes. MATROSHKA is a facility designed to determine the radiation exposure of an astronaut during an intra- and extravehicular activity at the International Space Station (ISS).

Short Description

The reference irradiations of the MATROSHKA phantom were carried out at the radiation standard laboratory in Seibersdorf and the nuclear research reactor at the Institute of Atomic and Subatomic Physics of the Vienna University of Technology. The measurements inside the phantom were accomplished with thermoluminescence dosimeters (TLDs) and an ionisation chamber for frontal and multidirectional incidence. During the previous project phase A a numerical model of the MATROSHKA phantom called MATSIM1.0 was developed using the Monte Carlo code FLUKA. FLUKA simulates the interaction and propagation of different particles, such as photons, electrons, hadrons, neutrons and heavy ions, in a wide energy range.

In addition to the established torso model of MATROSHKA, a high resolution voxel-based numerical model of the MATROSHKA head was developed in MATSIM-B. Both models are used to simulate the response of dosimeters within the MATROSHKA phantom. The congruence between the measured and simulated data is used to verify the numerical model. While in MATSIM-B the validation concerning neutrons and photons is carried out, further reference measurements have already been planned for proton and heavy ion radiation fields at a next project phase. Protons are the most important contribution to the space radiation environment. Heavy ions show the largest radio- biological effectiveness to tissue.

The MATSIM project will provide a validated and high resolution numerical voxel model of MATROSHKA. The model MATSIM1.0 will be used for space dosimetry to calculate the depth dose distribution within the phantom due to the complex radiation fields present at ISS, on Mars or for further space missions. The gained expertise is also important for cancer therapy and medical applications in proton and heavy ion dosimetry, which will be carried out at MedAustron in Austria.

Project Partners

Coordinator

AIT Austrian Institute of Technology GmbH, Health & Environment Department, Nano Systems Unit - Peter Beck, Sofia Rollet

Partners

Vienna University of Technology, Institute of Atomic and Subatomic Physics (ATI) - Ass.Prof. Michael Hajek
German Aerospace Center (DLR), Institute of Aerospace Medicine, Department for Radiation Biology - Günther Reitz, Thomas Berger
NASA, Johnson Space Center - Edward Semones

Contact Address

AIT Austrian Institute of Technology GmbH
Health & Environment Department
Nano Systems Unit
Peter Beck, Sofia Rollet
Donau-City-Straße 1
A-1220 Vienna
Tel.: +43 (505) 50 4305
E-mail: peter.beck@ait.ac.at
Web: www.ait.ac.at