Divertor design and its integration into ITER

The physics of the ITER edge and divertor plasma is strongly coupled with the divertor and the fuel cycle design. Owing to the limited space available the design as well as the remote maintenance approach for the ITER divertor are highly optimized to allow maximum space for the divertor plasma. Several auxiliary systems (e.g., in-vessel viewing instruments and glow discharge electrodes) as well as a part of the pumping and fuelling system have to be integrated together with the divertor into the lower level of ITER. Two main options exist for the choice of the plasma facing material in the divertor, i.e. tungsten and CFC. On the basis of already existing R and D results it is likely that the material choice will be mainly determined by physics considerations and material issues (e.g., C-T co-deposition). The requirements for the ITER fuel cycle arise from plasma physics as well as from the envisaged operation scenarios. Owing to the complex dynamic relationship of the fuel cycle subsystems among themselves and with the plasma, codes are employed for their optimization. These interacting issues are elaborated on the latest design status discussed. (author)