JT-60SA Magnet System Status

The JT-60SA experimental device will be the world's largest superconducting tokamak when it is assembled in 2019 in Naka, Japan (R = 3 m, a = 1.2 m). It is being constructed jointly by institutions in the EU and Japan under the Broader Approach agreement. Manufacturing of the six NbTi equilibrium field (EF) coils, which have a diameter of up to 12 m, has been completed. So far, 13 of the 18 NbTi toroidal field (TF) coils, each 7-m high and 4.5-m wide, have also been manufactured and tested at 4 K in a dedicated test facility in France. The first three of four Nb3Sn central solenoid (CS) modules have been completed, as have all of the copper in-vessel error field correction coils. Installation of the TF magnet, around the previously welded 340° tokamak vacuum vessel and its thermal shield, started at the end of 2016 and is currently underway. The TF magnet will in turn support the EF and CS coils.