| Contributors: |
Pamela, J; Solano, Er; Adams, Jm; Agarici, G; Agarici, M; Akhter, H; Albanese, R; Alberti, S; Allfrey, S; Alper, B; Alves, D; Amarante, J; Amerongen, Fv; Andrew, P; Andrew, Y; Ane, Jm; Angioni, C; Antonucci, C; Ambrosino, G; Apruzzese, G; Ariola, M; Artaserse, G; Artaud, Jf; Ascasibar, E; Asp, E; Axton, M; Baciero, A; Badarelli, M; Baity, W; Balbin, R; Balme, S; Barana, O; Baranov, Y; Barbato, E; Barnsley, R; Basiuk, V; Bateman, G; Baumel, S; Bayetti, P; Baylor, L; Beaumont, B; Beaumont, P; Becoulet, A; Becoulet, M; Bekris, M; Beldishevski, M; Bell, Ac; Bennet, P; BERGER BY, G; Berk, Hl; Bernabei, S; Bertalot, L; Bertrand, B; Beurskens, M; Bibet, P; Bickley, A; Bigi, M; Bilato, R; Blackman, T; Blanchard, P; Blum, J; Bolzonella, T; Bondeson, A; Bongers, W; Bonheure, G; Bonnin, X; Borass, K; Borba, D; Bosak, K; Bosia, P; Boyer, H; Bracco, G; Braithwaite, Gc; Breizman, Bn; Bremond, S; Brennan, Pd; Bresslau, J; Brezinsek, S; Brichero, B; Briscoe, F; Brix, M; Brolatti, G; Brown, Dpd; Bruggeman, A; Bruschi, A; Bryan, S; Brzozowski, J; Bucalossi, J; Buceti, G; Buckley, Ma; Budd, T; Budny, R; Buratti, P; Butcher, P; Buttery, Rj; Calabro, G; Nichols, Cjc; Callen, J; Campbell, D |
| Description: |
Scientific and technical activities on JET focus on the issues likely to affect the ITER design and operation. Our understanding of the ITER reference mode of operation, the ELMy H-mode, has progressed significantly. The extrapolation of ELM size to ITER has been re-evaluated. Neoclassical tearing modes have been shown to be meta-stable in JET, and their beta limits can be raised by destabilization (modification) of sawteeth by ion cyclotron radio frequency heating (ICRH). Alpha simulation experiments with ICRH accelerated injected 4 (He) beam ions provide a new tool for fast particle and magnetohydrodynamic studies, with up to 80-90% of plasma heating by fast 4 He ions. With or without impurity seeding, a quasi-steady-state high confinement (H(98) = 1), high density(n(e)/n(GW) = 0.9-1) and high beta (betaN = 2) ELMy H-mode has been achieved by operating near the ITER triangularity ( similar to 0.40-0.5) and safety factor (q(95) similar to 3), at Z(eff) similar to 1.5-2. In advanced tokamak (AT) scenarios, internal transport barriers (ITBs) are now characterized in real time with a new criterion, rhoT(*). Tailoring of the current profile with T lower hybrid current drive provides reliable access to a variety of q profiles, lowering access power for barrier formation. Rational q surfaces appear to be associated with ITB formation. Alfven cascades were observed in reversed shear plasmas, providing identification of q profile evolution. Plasmas with 'current holes' were observed and modelled. Transient high confinement AT regimes with H(89) = 3.3, beta(N) = 2.4 and ITER-relevant q < 5 were achieved with reversed magnetic shear. Quasi-stationary ITBs are developed with full non-inductive current drive, including similar to 50% bootstrap current. A record duration of ITBs was achieved, up to 11 s, approaching the resistive time. For the first time, pressure and current profiles of AT regimes are controlled by a real-time feedback system, in separate experiments. Erosion and co-deposition studies with a quartz ... |