Tearing mode rotation by external field in the RFX Reversed Field Pinch experiment
Abstract
We present the results of the first experiments on resistive tearing mode rotation control in the RFX reversed field pinch by an external m=0 magnetic field perturbation. In this way the helical deformation of the plasma column produced by resonant m=0 modes can be localized in a pre-selected toroidal position. We also show that a continuous toroidal rotation of this deformation can be induced by a rotating external field. Many different plasma conditions were explored in terms of plasma current, electron density, reversal parameter and perturbation amplitude. In this way were able to determine the parameters region where a continuous toroidal rotation of the helical deformation of the plasma column can be induced. From the study of such toroidal rotations the non linear origin of the torque acting on the internally resonant modes clearly emerges. In particular we demonstrate the occurrence of phase conjugation and harmonic generation phenomena. Different possible effects of the external rotating perturbation on modes amplitude and phasing have been observed and will be presented at the conference.
- Publication:
-
APS Division of Plasma Physics Meeting Abstracts
- Pub Date:
- November 1999
- Bibcode:
- 1999APS..DPP.GP164B