High internal inductance improved confinement <i>H</i>-mode discharges obtained with an elongation ramp technique in the DIII-D tokamak

L. L. Lao; J. R. Ferron; T. S. Taylor; K. H. Burrell; V. S. Chan; M. S. Chu; J. C. DeBoo; E. J. Doyle; C. M. Greenfield; R. J. Groebner; R. James; E. A. Lazarus; T. H. Osborne; H. St.John; E. J. Strait; S. J. Thompson; A. D. Turnbull; D. Wroblewski; H. Zohm; The DIII-D Team

doi:10.1103/PhysRevLett.70.3435

High internal inductance improved confinement H-mode discharges obtained with an elongation ramp technique in the DIII-D tokamak

L. L. Lao, J. R. Ferron, T. S. Taylor, K. H. Burrell, V. S. Chan, M. S. Chu, J. C. DeBoo, E. J. Doyle, C. M. Greenfield, R. J. Groebner, R. James, E. A. Lazarus, T. H. Osborne, H. St.John, E. J. Strait, S. J. Thompson, A. D. Turnbull, D. Wroblewski, H. Zohm, and The DIII-D Team

Phys. Rev. Lett. 70, 3435 – Published 31 May 1993

Abstract

High confinement mode (H-mode) discharges with peaked toroidal current density profile (high internal inductance, $l_{i}$ ) and improved confinement are obtained in the DIII-D tokamak by dynamically varying the current profile using a rapid elongation ramp technique. The confinement improvement increases with $l_{i}$ and persists in the presence of edge-localized modes. The plasma toroidal rotation and the corresponding radial electric field component also increase with the peakedness of the current density profile.