Nuclear analyses of some key aspects of the ITER design with Monte Carlo codes

The design of the ITER machine was presented in 2001 [1,2]. A nuclear analysis was performed at this time, using fairly detailed models and the best assessed nuclear data and codes that were available. As the construction phase of ITER is approaching, the design of the main components has been optimized/finalized and several minor design changes/optimizations have been made, some with the object to mitigate critical radiation shielding problems. These have required refined calculations to confirm that the nuclear design requirements are met. This paper reviews some of the most recent neutronic work with emphasis on critical nuclear responses in the TF coil inboard legs and vacuum vessel related to design modifications made to the blanket modules and vacuum vessel.