La stabilite du Kink interne dans les configurations helicoidales de grand rapport d'aspect (hx<<1)

TL;DR

This paper derives a stability criterion for the internal kink mode in large aspect ratio helicoidal configurations, highlighting the stabilizing influence of helicity, especially when the helicoidal pitch is small.

Contribution

It provides a general expression for the internal kink stability criterion in helicoidal discharges with finite helicity and large aspect ratio, emphasizing the stabilizing role of helicity.

Findings

Helicity has a stabilizing effect on the internal kink mode.

The stabilizing effect of helicity can surpass the toric effect.

Stability increases when the helicoidal pitch is smaller than the toric radius.

Abstract

We get the general expression for the stability criterion with respect to the internal kink under helicoidal discharges, if one assumes that the helicity is finite and the aspect ratio is large (hx<<1). We show that the helicity relative to the cylindric topology has a stabilizing effect. This effect can be greater than the toric effect when the helicoidal pitch is smaller than the toric radius.