Analysis of deviation from neoclassical ion equilibrium against electron and ion temperature profiles in T-10 tokamak

TL;DR

This study investigates how ion equilibrium deviations from neoclassical predictions in the T-10 tokamak relate to electron and ion temperature profiles, revealing significant electron contributions in various heating conditions.

Contribution

It introduces a combined local and nonlocal analysis of ion equilibrium deviations using direct electric field measurements and temperature profiles in the T-10 tokamak.

Findings

Electrons significantly contribute to ion equilibrium deviations.

Both local and nonlocal correlations are observed.

Deviations vary with different auxiliary heating levels.

Abstract

The results of the analysis of the deviation of the force equilibrium for ions from the neoclassical theory prediction, calculated using the direct measurements of the radial electric field, in the view of its possible local and nonlocal correlation with the profiles of electron, Te, and ion, Ti, temperatures in the T-10 tokamak are presented. Local correlations are analyzed by means of the Pearson's correlation. Nonlocal correlations are treated with an inverse problem under the assumption of an integral equation relationship between the deviation and Te and Ti profiles. The discharges with zero, weak and strong auxiliary heating (electron cyclotron resonance heating) are analyzed. It is found that the electrons substantially (not less than ions) contribute to the deviation of the ion equilibrium from the neoclassical theory prediction both in the local and nonlocal models.