Electron cyclotron stray radiation detection and machine protection system proposal for JT-60SA

The JT-60SA tokamak is scheduled to start operations in 2019 to support the ITER experimental programme and to provide key information for the design of DEMO scenarios. The device will count on ECRH and NBI as auxiliary heating. Potentially dangerous situations that could harm the tokamak structures during operations characterized by low EC absorption cannot be a priori excluded. An estimation of the wall load under direct beam exposure and during plasma operations will be given, using the EC antenna main characteristics and launching geometry. A system capable to prevent the risk of damage to machine components for JT-60SA is presented and examples of potential benefits of such a system will be given, based on recent experience gained on the TCV tokamak during EC wall cleaning experiments performed in preparation of JT-60SA operations.