Evaluation of Radiation Skyshine and Groundshine of a D-D Tokamak Using Monte Carlo Method

Computational analyses were performed to evaluate the radiation skyshine and groundshine from the D-D Tokamak EAST under various design cases. The Monte Carlo transport code MCNP-4C, the nuclear data library FENDL-2 and a simplified geometrical model were used. The influence of different filling materials for tokamak vacuum vessel and shielding hall roofs on the environmental dose rate distribution were investigated. The results indicate that the direct contribution to environmental radiation from the D-D neutron source decreases rapidly with the radial distance increasing and then the skyshine radiation dominates. In addition, the groundshine effect makes significant contribution to the environmental radiation