Kink instability

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

A kink instability, also oscillation or mode, is the m=1 class of magnetohydrodynamic instabilities which sometimes develop in a thin plasma column carrying a strong axial current. If a "kink" begins to develop in a column the magnetic forces on the inside of the kink become larger than those on the outside, which leads to growth of the perturbation.^[1] As it develops at fixed areas in the plasma, kinks belong to the class of "absolute plasma instabilities", as opposed to convective processes. The kink instability was first widely explored in the Z-pinch fusion power machines in the 1950s.

References

1. Plasma Dictionary