TARGET PLASMA CONDITIONS IN TCA
We discuss the conditions of the target plasma in the TCA tokamak prior to the rf heating pulse. The toroidal field and plasma current are held fixed and the density is varied from p-delta n-e about 0.5x10**13 to 5x10**13 cm**- 3-. Both hydrogen and deuterium discharges are considered. The density and gas dependence of the macroscopic plasma parameters is analyzed, as well as the impurity and energy content. We observe an increasing peaking of the electron density profile as the density is increased. This observation is compatible with other small Tokamaks and we present a density profile scaling law that depends on the Murakami parameter n-e(0)R-0/B-phi. We find that for this range of density, the global energy confinement time is proportional to the line density as is typically the case before the saturation of Alcator Scaling which provides an adequate representation of the data. We perform a radial electron power balance in order to estimate the electron thermal conductivity n-e/chi-e. Its value at half radius is around 4x10**17 cm**-1-s**-1 for the lowest density discharges and decreasing to 2x10**17 cm**-1 x s**-1 at the highest density. The diagnostics used for this study are also briefly described, together with their analysis techniques.
Bibliographic Reference: WRITE TO CENTRE DE RECHERCHES EN PHYSIQUE DES PLASMAS, ECOLE POLYTECHNIQUE FEDERALE DE LAUSANNE, 21, AVENUE DES BAINS, CH-1007 LAUSANNE (SWITZERLAND), MENTIONING REPORT LRP 241/84, 1984
Record Number: 1989123036500 / Last updated on: 1987-01-01
Available languages: en