Advancement of Nuclear Analysis Method for ITER

Advancement of nuclear analyses, which means improvement and validation of radiation transport codes and nuclear data libraries, is a key issue for ITER licensing. Thus we have developed an automatic conversion system in order to easily make precise geometry input data of radiation transport codes from CAD data even for complicated ITER structures. We also applied this system to the ITER 40 degree benchmark model for validation and compared our results with those by other ITER participating parities (China, EU, US). We also performed a narrow slit streaming experiment for analysis validation on streaming effects at JAEA/FNS and verified the prediction accuracy of neutron transport calculations with the MCNP4C, TORT and Attila codes.