Scaling of energy confinement time with the minor radius in the FT tokamak

Abstract

The scaling of the electron energy confinement time with the plasma minor radius, derived from FT data only, does not agree with that obtained by comparing the same data with experimental results from other devices. It is shown that, by taking into account the systematic difference in the measured density profiles for different limiter radii in FT, this apparent disagreement vanishes. The resulting scaling with the minor radius in FT is also consistent with the scalings derived by comparison of a wide variety of Ohmically heated tokamak discharges.