On the mutual effect of ion temperature gradient instabilities and impurity peaking in the reversed field pinch

TL;DR

This paper investigates how impurities influence ion temperature gradient instabilities and turbulence in the reversed field pinch device RFX-mod, revealing their destabilizing role and compatibility with observed impurity profiles.

Contribution

It provides the first detailed analysis of impurity effects on ITG instabilities in RFX-mod, combining gyrokinetic calculations with experimental impurity profiles.

Findings

Impurities destabilize ITG modes in RFX-mod.

ITG turbulence can coexist with hollow impurity profiles.

Impurities influence turbulence characteristics in reversed field pinches.

Abstract

The presence of impurities is considered in gyrokinetic calculations of ion temperature gradient (ITG) instabilities and turbulence in the reversed field pinch device RFX-mod. This device usually exhibits hollow Carbon/Oxygen profiles, peaked in the outer core region. We describe the role of the impurities in ITG mode destabilization, and analyze whether ITG turbulence is compatible with their experimental gradients.