Experimental studies of ITER demonstration discharges

Sips, A. C. C.*; Casper, T. A.*; Doyle, E. J.*; Giruzzi, G.*; Gribov, Y.*; Hobirk, J.*; Hogeweij, G. M. D.*; Horton, L. D.*; Hubbard, A. E.*; Hutchinson, I.*; Ide, Shunsuke; Isayama, Akihiko; Imbeaux, F.*; Jackson, G. L.*; Kamada, Yutaka; Kessel, C.*; Kochl, F.*; Lomas, P.*; Litaudon, X.*; Luce, T.*; Marmar, E.*; Mattei, M.*; Nunes, I.*; Oyama, Naoyuki; Parail, V.*; Portone, A.*; Saibene, G.*; Sartori, R.*; Suzuki, Takahiro; Tardini, G.*; Wolfe, S. M.*

The ITER discharge evolution has been verified in dedicated experiments. Results show that breakdown at E 0.23-0.32 V/m is possible un-assisted (ohmic) for large devices like JET and attainable in all devices with ECRH assist. For the current ramp up, good control of the plasma inductance is obtained using a full bore plasma shape with early X-point formation. Operation of the H-mode reference scenario at q = 3 and the hybrid scenario at q95=4-4.5 during the flat top phase was documented. Specific studies during the flat top phase provide data for the li evolution after the H-mode transition and the li evolution after a back-transition to L-mode. During the ITER ramp down it is important to remain diverted and to reduce the elongation.