Hostname: page-component-586b7cd67f-dsjbd Total loading time: 0 Render date: 2024-11-26T01:31:47.570Z Has data issue: false hasContentIssue false

Thermal instability excited in the electron-cyclotron resonance heating of plasmas

Published online by Cambridge University Press:  13 March 2009

S. P. Kuo
Affiliation:
Weber Research Institute, Polytechnic University, Farmingdale, Ney York 11735, U.S.A.
M. C. Lee
Affiliation:
Plasma Fusion Center, Massachusetts Institute of Technology, Cambridge, Massachusetts 02319, U.S.A.

Abstract

A thermal instability is studied as an explanation of the anomalous electron density depletion observed during the electron-cyclotron resonance (ECR) heating of plasma in a tokamak device for an impurity study experiment (ISXB). Considering the fact that the background plasma has an elevated electron temperature and a localized heat source located near the ECR layer, we show that density striations having scale length 10 cm and larger can be excited via the thermal instability. The amplitude of the striations can grow by more than one e-folding during the ECR pulse period of 10 ms, which causes about 50% electron temperature elevation. A 0·1% temperature fluctuation excited by the thermal instability leads to about 50 V m-1 field fluctuation. Such a large electrostatic field can effectively cause anomalous plasma diffusion via the EB drift and account for the observed 15% electron density depletion.

Type
Research Article
Copyright
Copyright © Cambridge University Press 1993

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

REFERENCES

Alikaev, V. V., Bobrorskii, G. A., Poznyak, V. Z., Razumova, K. A., Sannikov, V. V., Sokalov, Yu. A. & Shmarin, A. A. 1976 Soviet J. Plasma Phys. 2, 212.Google Scholar
Antonson, T. M. & Manheimer, W. M. 1978 Phys. Fluids 21, 2295.Google Scholar
Bragonskii, S. I. 1965 Reviews of Plasma Physics, vol. 1 (ed. Leontovich, M. A.), p. 205. Consultants' Bureau.Google Scholar
Carmel, Y., Chu, K. R., Read, M., Ganguly, A. K., Dialens, D., Seeley, R., Levine, J. S. & Granatstein, V.L. 1983 Phys. Rev. Lett. 50, 112.Google Scholar
Chu, K. R. & Hui, B. 1983 Phys. Fluids 26,69.Google Scholar
Dandl, R. A., Baity, F. W., Cartenter, K. H., Cobble, J. A., Eason, H. O., Glowienka, J. C., Haste, G. H., Hess, M. E., Hiroe, S., Lazer, N. H., Quon, B. H., Uckan, T., White, T. L., Bieniosek, F. M., Bresnock, F. J., Colestock, P. L., Conner, K. A., Htckok, R. L., Kuo, S., Moos, H. W., Tyson, J. M., Warden, E. S., Hedrick, C. L.,Batchelor, D. B., Deleano, L., Goldfinger, R. C., Jaeger, E. F., Owen, L. W., Spong, D. A., Tolliver, J. S., McBride, J. B., Krall, N. A. & Sulton, L. 1979 Plasma Physics and Controlled Nuclear Fusion Research, vol. 2, p. 365. IAEA.Google Scholar
Djuth, F. T., Thide, B., Terkic, H. M. & Sulzer, M. P. 1987 Geophys. Res. Lett. 14, 953.Google Scholar
Eldridge, O. 1972 Phys. Fluids 15, 676.Google Scholar
England, A. C. 1984 IEEE Trans. Plasma Sci. 12, 124.Google Scholar
Gilgenbach, R. M., Read, M. E., Hackett, K. E., Lucey, R., Hui, B., Granatstein, V. L., Chu, K. R., England, A. C., Loring, C. M., Eldridge, O. C., Howe, H. C., Kulchar, A. G., Lazarus, E., Murakami, M. & Wilgen, J. B. 1980 Phys. Rev. Lett. 44, 647.Google Scholar
Hoshino, K., Yamamoto, T., Funahashi, A., Suzuki, N., Matoba, T., Yamauchi, T., Matsumoto, H., Kawakami, T., Kimura, H., Konoshita, S., Maeno, M., Matsuda, T., Matsuzaki, Y., Odashima, K., Ohasa, K., Sengoku, S., Shoji, T., Sugie, T., Yamamoto, S., Tanaka, T., Moeller, C. P., Lattaye, R. J. & Prater, R. 1985 J. Phys. Soc. Japan 54, 2503.Google Scholar
Hsu, J. Y. & Chiu, S. C. 1980 Phys. Rev. Lett. 45, 1561.Google Scholar
Kreischer, K. E. & Ternkin, R. J. 1987 Phys. Rev. Lett. 59, 547.Google Scholar
Kuo, S. P. & Cheo, B. R. 1981 Phys. Fluids 24, 784.Google Scholar
Kuo, S. P. & Cheo, B. R. 1983 Phys. Fluids 26, 3018.Google Scholar
Kuo, S. P. & Djuth, F. T. 1988 Geophys. Res. Left. 15, 1345.Google Scholar
Meoller, C. P., Chan, V. S., Lahaye, R. J., Prater, R., Yamamoto, T., Funahashi, A., Hoshino, K. & Yamouchi, T. 1982 Phys. Fluids 25, 1211.Google Scholar