OVERVIEW OF THE JET PREPARATION FOR DEUTERIUM-TRITIUM OPERATION

For the past years, the JET scientific Programme [1] is engaged in a multi-campaigns effort including experiments in D, H and T, leading up in 2020 to the first experiments in D-T mixtures since 1997 and the first ever D-T plasmas with the ITER mix of plasma-facing component materials. For this purpose, a concerted physics and technology programme was launched in view of preparing the DT campaign (DTE2). This paper addresses the key elements developed by the JET programme directly contributing to the DT preparation. This intense preparation includes the review of the physics basis for the D-T operational scenarios, including the fusion power predictions through first principle and integrated modelling and the impact of isotopes in the operation and physics of D-T plasmas (thermal and particle transport, H-mode access, Be & W erosion, fuel recovery, etc.). This effort also requires improving several aspects of plasma operation for DTE2, such as real time control schemes, heat load control, disruption avoidance and mitigation system (including the installation of a new shattered pellet injector), novel ion cyclotron resonance heating (ICRH) schemes (such as the three-ions scheme), new diagnostics (neutrons camera and spectrometer, active Alfvèn Eigen-modes antennas, neutral gauges, radiation hard imaging systems ...) and the calibration of the JET neutron diagnostics at 14 MeV for the accurate fusion power measurement. The active preparation of JET for the 2020 DT campaign provides an incomparable source of information and basis for the future DT operation of ITER and it is also foreseen that a large number of key physics issues will be addressed in support of burning plasmas.