Progress Using LHCD and ICRF on Advanced Tokamak Discharges in Alcator C-Mod

POSTER

Abstract

Advanced tokamak discharges on Alcator C-Mod are targeting high non-inductive current fraction with bootstrap and lower hybrid (LH) current drive, and high confinement from ICRF heated H-modes. Plasma currents in the range of 450-600 kA are coupled with up to 3.5 MW of ICRF and 0.6-0.9 MW of LH. Longer plasma current rampup times are used to allow the ICRF and LH to modify the current profile. Delay of the sawtooth onset is significant using the LH by itself and in combination with the ICRF. ICRF H-modes in the rampup show they are not as effective at delaying the sawtooth as LH. Time dependent simulations of the discharges with the TSC and LSC code (ray-tracing with 1D FP) have helped to determine the magnitude of the LHCD and the resulting effects on the safety factor profile. Analysis with GENRAY-CQL3D (ray-tracing with 2D FP) will be given.

Authors

  • Charles Kessel

    PPPL, Princeton Plasma Physics Laboratory

  • Amanda Hubbard

    MIT PSFC, MIT

  • P.T. Bonoli

    MIT PSFC, PSFC-MIT, MIT, MIT Plasma Science and Fusion Center, PSFC, MIT, Cambridge, MA

  • R.R. Parker

    MIT PSFC, MIT

  • Yijun Lin

    MIT Plasma Science and Fusion Center, MIT PSFC

  • A.E. Schmidt

    MIT PSFC

  • S. Scott

    PPPL

  • Syun'ichi Shiraiwa

    MIT PSFC, PSFC, MIT

  • Adrianus Sips

    Max Planck IPP, Max-Planck-Inst. fur Plasmaphysik, Euratom Assoc., Garching, Germany

  • Greg Wallace

    MIT Plasma Science and Fusion Center, MIT PSFC, MIT

  • R. Wilson

    PPPL

  • Steve Wolfe

    MIT, MIT PSFC, MIT, Plasma Science and Fusion Center

  • Steven Wukitch

    MIT Plasma Science and Fusion Center, MIT PSFC, MIT-PSFC, MIT, Plasma Science and Fusion Center