Initial Results from the Tokapole-II Poloidal Divertor Device
A. P. Biddle, R. N. Dexter, R. J. Groebner, D. J. Holly, B.
M. W. Phillips, S. C. Prager, J. C. Sprott
University of Wisconsin, Madison,
Wisconsin, United States of America
(Manuscript received 30 March 1979; Final version received 7 July 1979)
The latest in a series of internal-ring devices, called Tokapole II,
recently begun operation at the University of Wisconsin. Its purpose is
to permit the study of the production and confinement of hot, dense
in either a toroidal octupole (with or without toroidal field) or a
with a four-node poloidal divertor. The characteristics of the device
the results of its initial operation are described here. Quantitative
of impurity concentration and radiated power have been made. Poloidal
equilibia of square and dee shapes have been produced, and an
instability has been observed with the inverse dee. Electron cyclotron
resonance heating is used to initiate the breakdown near the axis and
control the initial influx of impurities. A 2-MW RF source at the
harmonic of the ion cyclotron frequency is available and has been used
to double the ion temperature when operated at low power with an
antenna. Initial results of operation as a pure octupole with poloidal
Ohmic heating suggest a tokamak-like scaling of density (n ~ Bp) and
time (tau ~ n).
Ref: A. P. Biddle, R. N. Dexter, R. J. Groebner, D. J. Holly, B.
M. W. Phillips, S. C. Prager, and J. C. Sprott,
Fusion 9, 1509-1518 (1979)
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