THE INFLUENCE OF RESONANT HELICAL FIELDS ON TOKAMAK CONFINEMENT
Experiments have been performed on the TOSCA Tokamak to investigate the influence of magnetic perturbations on confinement. The perturbations are either imposed, via external windings, or natural plasma fluctuations. Large applied m = 2, n = 1 fields stop the m = 2, n = 1 oscillations and reduce the amplitude of the broad-band radial field perturbations b-r. The size of the imposed magnetic islands depends upon the response of the plasma. Measurements indicate that there is an enhancement of the applied field. Theoretical predictions depend critically upon details of the current profile. The effect of finite conductivity is considered. The magnetic power spectrum has been measured as a function of radius and density. The global energy confinement appears to be independent of b-r. Large fluctuations (<=40 V), correlated with m = 2, n = 1 activity, are seen on the floating potential of the limiters.
Bibliographic Reference: 10TH INTERNATIONAL CONFERENCE ON PLASMA PHYSICS AND CONTROLLED NUCLEAR FUSION RESEARCH, LONDON (UK), SEPT. 12-19, 1984 PUBLISHED BY IAEA, WIEN (AUSTRIA), 1985, VOL. 1, PP. 363-371
Record Number: 1989124026500 / Last updated on: 1987-01-01
Available languages: en