Speaker
Description
As a response to an ESA call a contracted R&D activity is running with ambition to develop new efficient, lightweight radiation shielding solution for electronic components on GEO telecommunication satellites. Based on physical understanding of interactions of different kind of radiations with different target materials our idea is to use optimized combination of low and high Z materials either in a multilayer stack or composite structure. Both the geometrical and material thickness of the shielding is constrained by an equivalent of 5 mm (1.35 g/cm2) of aluminum. For the optimization we have used the relevant space radiation environment in GEO including trapped electrons and mission fluence of solar particle event protons. The Geant4, HZETRN2015 and Shieldose2 transport codes were used for model calculations. For optimization purpose the total ionizing dose in silicon-dioxide was selected as response parameter. With the same areal mass density as of 5 mm aluminum we predicted around 45% dose reduction using our optimized configuration. Our novel shielding stacks were already tested for total ionizing dose reduction capabilities using electrons from a LINAC electron accelerator with degraded energy from a 6 MeV nominal energy. Our shielding stacks have been proven to perform accordingly to model simulations and for this particular radiation field they reached nearly 70% dose reduction when compared to aluminum.
