Works on ITER prototypes at SCK CEN in 2021: Scientific report 2021

Since a number of years the SCK CEN is participating in the development of the fibre optics sensor (FOCS) capable to measure the plasma current in magnetic fusion devices. The operation of this sensor is based on the Faraday effect, which allows accurate measurements for a steady-state conditions. Thanks to the SCK CEN efforts FOCS is included in the ITER diagnostics’ suite. The current goals are to assist implementation of the FOCS in ITER, to improve the FOCS performance characteristics, and to explore the possibilities which the installation of an optical fibre on a tokamak may offer, for example to perform distributed magnetic field measurements. Installation and operation of FOCSs at JET and WEST are important support activities. This work is possible thanks to the support from the Belgian Government for the development of ITER prototypes, ITER support, and Eurofusion projects. The present report provides an account of works performed during the calendar year 2021, including Management, FOCS R&D, collaboration with JET and ITER.