Benchmarking the MCR2S system for high-resolution activation dose analysis in ITER

The MCR2S system is a tool for the analysis of activation dose in ITER and fusion devices based on the rigorous-2-step formalism, MCNP mesh-tallies and the FISPACT nuclear inventory code. It couples transport and activation calculations in an integrated manner, allowing for the necessarily fine energy and spatial resolutions required for this kind of analysis and overcoming limitations of previous similar tools. The system is routinely used at UKAEA to assist the design of several ITER components such as the ICRH heating system and LIDAR diagnostic. Here we describe its functionality and a first benchmark exercise performed using the fusion-relevant Frascati Neutron Generator shutdown dose rate experiment results. Neutron spectra, reaction rates, photon spectra and activation decay dose rates at several positions and times, obtained using FENDL-2.1/MC and EAF-2007 data, are presented and compared to those of earlier software and libraries, showing good agreement. C/E values close to unity are obtained in all cases, illustrating the robustness and reliability of this novel software.