Hill, K. W., Biglari, H., Bitter, M., Barnes, C., Cranmer, S. R., von Goeler, S. R., Goldston, R., Grek, B., Hsuan, H., Johnson, D., Stevens, J., Taylor, G., Zweben, S. 1989, "Search for a Suprathermal Tail on TFTR Soft X-Ray Spectra, and Implications for Transport," Bull. Am. Phys. Soc., 31st Annual Meeting of the Division of Plasma Physics, 3F6, p. 1964.
ABSTRACT:
The degree of distortion of the electron distribution function from Maxwellian may indicate whether the transport is predominantly electrostatic or electromagnetic. A bump on the tail of the distribution function at E / Tc ~ R / Ln would be evidence of (electrostatic) collisionless trapped electron mode turbulence. In previous experiments non-thermal spectra in T-10 and Alcator-A were interpreted, respectively, as evidence of magnetic-ripple- and magnetic-fluctuation-driven transport. Soft x-ray spectra from three chords of ohmic and beam-heated TFTR discharges are examined up to 50 keV for evidence of non-thermal distributions. The x-ray temperatures are compared with Thomson-scattering data. The theoretical bases for the above interpretations, and the TFTR data will be discussed.