Il Nuovo Cimento D

, Volume 15, Issue 7, pp 1009–1016 | Cite as

Analysis of electron cyclotron emission by lower-hybrid current drive plasmas

  • A. Airoldi
  • G. Ramponi
Article

Summary

Electron cyclotron emission may be used for diagnosing non-thermal electron distribution functions generated by radio-frequency current drive. Our attention is concentrated in theX-mode-downshifted second-harmonic range of frequencies, by inspecting at the radiation collected in the horizontal low-magnetic-field side of a tokamak. The cut-off presence eliminates the thermal first-harmonic emission and the non-thermal one may be observed without other inference. The electron distribution function is modelled by a suitable sum of drifting Maxwellians for reproducing the flat tails usually obtained in the presence of lower-hybrid power injection. This model is time saving as far as the computer simulations are concerned and permits a lot of runs in order to accomplish a wide parameters exploitation. A sensitivity analysis of ECE intensity is performed with respect to the main moments of the suprathermal electrons distribution function. The analysis shown that the radiation spectra are very sensitive to the perpendicular energy and to the number of fast electrons, while only a weak dependence on the parallel energy is found.

PACS 52.25.Sw

Emission absorption and scattering of radio-wave and microwave radiation 

Preview

Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.

References

  1. [1]
    P. T. Bonoli andR. C. Englade:Phys. Fluids,29, 2937 (1986).MATHCrossRefADSGoogle Scholar
  2. [2]
    G. Taylor et al.: Proceedings of the XVI EPS, Venice, March 13–17, 1989, Vol. 13B, Part I, p. 31.Google Scholar
  3. [3]
    S. Ide et al.:Nucl. Fusion,29, 1325 (1989).Google Scholar
  4. [4]
    K. Kato andI. H. Hutchinson:Phys. Fluids,30, 3809 (1987).CrossRefADSGoogle Scholar
  5. [5]
    L. Rodriguez et al.:Proceedings of the XVIII EPS, Berlin, 3–7 June, 1991, Vol. 15C, Part IV, p. 353.Google Scholar
  6. [6]
    A. Airoldi, A. Orefice andG. Ramponi:Proceedings of the VII Joint Workshop and IAEA Technical Meeting on ECE and ECRH, Hefei (China), 1989, p. 20.Google Scholar
  7. [7]
    A. Airoldi, A. Orefice andG. Ramponi:Nuovo Cimento D,13, 517 (1991)CrossRefGoogle Scholar
  8. [8]
    A. Airoldi, A. Orefice andG. Ramponi:Nuovo Cimento D,6, 527 (1985).CrossRefGoogle Scholar
  9. [9]
    A. Orefice:Nuovo Cimento D,12, 1575 (1990).CrossRefGoogle Scholar
  10. [10]
    A. Orefice:Nuovo Cimento D,8, 318 (1986).CrossRefGoogle Scholar
  11. [11]
    G. Gormezzano et al.:Proceedings of the XVIII European Conference on Controlled Fusion and Plasma Physics, ECA, Vol. 15C, Part III, p. 393 (Berlin, 1991).Google Scholar
  12. [12]
    G. Ramponi et al.:Proceedings of the 1992 International Conference on Plasma Physics, ECA, Vol. 16C, Part II, p. 973 (Innsbruck, 1992).Google Scholar

Copyright information

© Società Italiana di Fisica 1993

Authors and Affiliations

  • A. Airoldi
    • 1
  • G. Ramponi
    • 1
  1. 1.Istituto di Fisica del PlasmaAssociazione EURATOM/CNR/ENEAMilanoItalia

Personalised recommendations