Contribution to the 22. IAEA Fusion Energy Conference

This report is a compilation of the papers, concerning the FAST (Fusion Advanced Studies Torus) proposal, presented to the 22. IAEA conference on Fusion Energy. FAST is a new machine proposed to support ITER experimental exploitation as well as to anticipate DEMO relevant physics and technology. FAST is aimed at studying, in burning plasma relevant conditions, fast particle physics, plasma operations and plasma wall interaction in an integrated way. FAST has the capability to approach all the ITER scenarios significantly closer than present day experiments by using Deuterium plasmas. The necessity of achieving ITER relevant performance with a moderate cost has led to conceiving a compact Tokamak (R=1.82 m, a= 0.64 m) with high toroidal field (BT up to 8.5 T) and plasma current (Ip up to 8 MA). In order to study fast particle behaviours in conditions similar to those of ITER, the project has been provided with a dominant Ion Cyclotron Resonance Heating System (ICRH; 30 MW on the plasma). Moreover, the experiment foresees the use of 6 MW of Lower Hybrid (LHCD), essentially for plasma control and for non-inductive Current Drive, and of Electron Cyclotron Resonance Heating (ECRH, 4MW) for localized electron heating and plasma control. The ports have been designed to accommodate up to 10 MW of negative beams (NNBI) in the energy range of 0.5-1 MeV. The total power input will be in the 30-40 MW range in the different plasma scenarios with a wall power load comparable with that of ITER (P/R∼22 MW/m). All the ITER scenarios will be studied: from the reference H-mode, with plasma edge and ELMs characteristics similar to the ITER ones (Q up to ≅ 2.5), to a full current drive scenario, lasting around 170 s. The first wall as well as the divertor plates will be of Tungsten in order to ensure reactor relevant operation regimes. The divertor itself is designed to be completely removable by remote handling. This will allow studying (in view of DEMO) the behaviour of innovative divertor concepts, such as those based on liquid Lithium. FAST is capable of operations with very long pulses, up to 170 s, despite that it is a copper machine. The magnets initial operation temperature is 30 K, with cooling realised by helium gas. The in vessel components, namely first wall and divertor, are actively cooled by pressurised water at 80 0C. The same water is also used to back up the vacuum vessel. FAST is equipped with ferromagnetic inserts to keep the toroidal field magnet ripple down to 0.3%