Space Radiation Analysis: Radiation Effects and Particle Interaction outside Earth Magnetosphere using GRAS and GEANT4
- Paper number
IAC-10.A1.4.7
- Author
Mr. Lisandro Martinez, Cranfield University, Argentina
- Year
2010
- Abstract
A detailed analysis of galactic cosmic rays (GCR), solar proton events (SPE), and solar fluence effects have been conducted using SPENVIS and CREME96 data files for particle flux outside the Earth’s magnetosphere. The simulation was conducted using GRAS, a European Space Agency (ESA) software based on GEANT4. GRAS-GEANT4 simulations of the proton, He, and Fe induced radiation inside the ISS/TransHab models have been calculated; the initial approximation (simple models) used during this simulation intend to set a starting point for future, more detailed and realistic simulations incorporating user friendly design software to allow the development of more accurate environmental and geometrical models. Galactic cosmic rays total dose and dose equivalent rates produced by GRAS calculations were compared to experimental and modeled rates during solar maximum and minimum. The results obtained from isotropic random particle fluxes have been found to be larger to the ones resulted from simulation and experimental models inside the magnetosphere. These results coincide with the expected results and indicate the necessity to extend this research into a higher accuracy simulation to be able to provide realistic and comparable results for future space missions. The calculated dose rate from GCRs at solar max inside the ISS model is 395.18 RGy/d, while inside the TransHab structure are 1054 RGy/d. While SPEs worst day case effects inside the ISS are 1322 RGy/d, they are 1649.1 RGy/d inside the TransHab model. These results were comparable with previous simulations and demonstrated a correlation with respect of the previous differences between experimental and modeled data presented by T. Ersmark [Geant4 Monte Carlo Simulations of the International Space Station Radiation Environment]. The discrepancies found can be expected due to the geometrical model inaccuracies as well as the physics model energy limitation and the computational power restriction during this work. Therefore, the results from this simulation do not represent an accurate model for radiation deposition and particle modeling for deep space missions, but it represents a good model to analyze the effect of high-energy particles on different materials and gives a first degree approximation to the radiation effects on humans. The observed results during the analysis indicate that the inflatable TransHab structure may not provide enough shielding to the crew as is and extra shielding should be expected. On the other hand the ISS model represents a better shielding option but a robust and inconvenient structure for human exploration. Poster Session
- Abstract document
- Manuscript document
IAC-10.A1.4.7.pdf (🔒 authorized access only).
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