This work discusses a possible mechanism of spontaneous, triggerless onset of NTMs, observed sometimes on JET, associated with changes in the plasma rotation. The NTM onset threshold is associated with the ion polarisation current: this current can be either stabilizing or destabilizing depending on island rotating in the ion or electron diamagnetic drift direction, and is dependent on to the viscous regimes. Since in the nonlinear stage the magnetic islands necessarily break the ideal tokamak axisymmetry, a Neoclassical Toroidal Viscosity (NTV) appears in the toroidal direction, eventually determining self-consistently the magnetic island propagation speed.
|Publication status||Published - 2009|
|Event||36th European Physical Society Conference on Plasma Physics 2009, EPS 2009 - , Bulgaria|
Duration: 1 Jan 2009 → …
|Conference||36th European Physical Society Conference on Plasma Physics 2009, EPS 2009|
|Period||1/1/09 → …|
All Science Journal Classification (ASJC) codes
- Atomic and Molecular Physics, and Optics
Lazzaro, E., Nowak, S., Cirant, S., Coelho, R., & Buratti, P. (2009). Rotation and stability of magnetic islands in neoclassical viscous regimes. Paper presented at 36th European Physical Society Conference on Plasma Physics 2009, EPS 2009, Bulgaria.