Kink instability

A kink instability (also known as a kink oscillation or kink mode) is a current-driven plasma instability characterized by transverse displacements of a plasma column's cross-section from its center of mass without any change in the characteristics of the plasma.

It typically develops in a thin plasma column carrying a strong axial current which exceeds the Kruskal–Shafranov limit[1][2][3] and is sometimes known as the Kruskal–Shafranov (kink) instability,[4][5] named after Martin David Kruskal and Vitaly Shafranov.

The kink instability was first widely explored in fusion power machines with Z-pinch configurations in the 1950s.

[6] It is one of the common magnetohydrodynamic instability modes which can develop in a pinch plasma and is sometimes referred to as the

[6][7] As it develops at fixed areas in the plasma, kinks belong to the class of "absolute plasma instabilities", as opposed to convective processes.

One of the earliest photos of the kink instability in action - the 3 by 25 cm pyrex tube at Aldermaston.