Reimerdes H, Chu M S, Garofalo A M, Jackson G L, La Haye R J, Navratil G A, Okabayashi M, Scoville J T, Strait E J
Columbia University, New York, New York, USA.
Phys Rev Lett. 2004 Sep 24;93(13):135002. doi: 10.1103/PhysRevLett.93.135002. Epub 2004 Sep 20.
The stability of the resistive-wall mode (RWM) in DIII-D plasmas above the conventional pressure limit, where toroidal plasma rotation in the order of a few percent of the Alfve n velocity is sufficient to stabilize the n=1 RWM, has been probed using the technique of active MHD spectroscopy at frequencies of a few Hertz. The measured frequency spectrum of the plasma response to externally applied rotating resonant magnetic fields is well described by a single-mode approach and provides an absolute measurement of the damping rate and the natural mode rotation frequency of the stable RWM.
