Speaker
Description
The accurate assessment of radiation shielding performance is a key challenge in space mission design, requiring advanced modelling capabilities to capture complex particle interactions. Within ESA, a suite of simulation tools based on the Geant4 Monte Carlo framework has been developed to support shielding analysis, instrument response modelling, and radiation effects studies across a wide range of applications.
This contribution presents an overview of ESA’s Geant4-based tools, with particular focus on MULASSIS and GRAS. MULASSIS provides a robust and accessible environment for rapid evaluation of multi-layer shielding configurations using simplified geometries, while retaining detailed physics modelling and enabling analyses such as total ionising dose and non-ionising energy loss. Complementary non-Monte Carlo approaches further extend its applicability to fast parametric studies. In parallel, GRAS offers a highly flexible, multi-purpose simulation framework capable of handling complex three-dimensional geometries, advanced variance reduction techniques, and detailed detector response analyses for both scientific and engineering applications.
Recent developments include improved computational performance, enhanced physics modelling options, and integration within a broader ecosystem of tools and models, enabling end-to-end radiation environment and effects simulations. These capabilities support applications ranging from spacecraft shielding optimisation to radiation monitor design and human spaceflight studies.
The presentation highlights how these tools contribute to a consistent and scalable approach to radiation shielding analysis, bridging simplified and high-fidelity simulations within a unified Geant4-based framework.