Initial results from the Tokapole-II poloidal divertor device

A. P. Biddle, R. N. Dexter, R. J. Groebner, D. J. Holly, B. Lipschultz, M. W. Phillips, S. C. Prager, J. C. Sprott

Research output: Contribution to journalArticle

14 Scopus citations

Abstract

The latest in a series of internal-ring devices, called Tokapole II, has recently begun operation at the University of Wisconsin. Its purpose is to permit the study of the production and confinement of hot, dense plasmas in either a toroidal-octupole (with or without toroidal field) or a tokamak with a four-node poloidal divertor. The characteristics of the device and the results of its initial operation are described here. Quantitative measurements of Impurity concentration and radiated power have been made. Poloidal divertor equilibria of square and dee shapes have been produced, and an axisymmetric instability has been observed with the inverse dee. Electron cyclotron resonance heating is used to initiate the breakdown near the axis and to control the initial influx of impurities. A 2-MW RF source at the second harmonic of the ion cyclotron frequency is available and has been used to double the ion temperature when operated at low power with an unoptimized antenna. Initial results of operation as a pure octupole with poloidal Ohmic heating suggest a tokamak-like scaling of density (n ∝ Bp) and confinement time (τ ∝ n).

Original languageEnglish (US)
Pages (from-to)1509-1518
Number of pages10
JournalNuclear Fusion
Volume19
Issue number11
DOIs
StatePublished - Nov 1979
Externally publishedYes

All Science Journal Classification (ASJC) codes

  • Condensed Matter Physics
  • Nuclear and High Energy Physics

Fingerprint Dive into the research topics of 'Initial results from the Tokapole-II poloidal divertor device'. Together they form a unique fingerprint.

  • Cite this

    Biddle, A. P., Dexter, R. N., Groebner, R. J., Holly, D. J., Lipschultz, B., Phillips, M. W., Prager, S. C., & Sprott, J. C. (1979). Initial results from the Tokapole-II poloidal divertor device. Nuclear Fusion, 19(11), 1509-1518. https://doi.org/10.1088/0029-5515/19/11/010