Bergerson W F, Forest C B, Fiksel G, Hannum D A, Kendrick R, Sarff J S, Stambler S
Department of Physics, University of Wisconsin, 1150 University Avenue, Madison, WI 53706, USA.
Phys Rev Lett. 2006 Jan 13;96(1):015004. doi: 10.1103/PhysRevLett.96.015004. Epub 2006 Jan 4.
An internal kink instability is observed to grow and saturate in a line-tied screw pinch plasma. Detailed measurements show that an ideal, line-tied kink mode begins growing when the safety factor q = (4pi2r2B(z))/(mu0I(p)(r)L) drops below 1 inside the plasma; the saturated state corresponds to a rotating helical equilibrium. In addition to the ideal mode, reconnection events are observed to periodically flatten the current profile and change the magnetic topology.
