Stabilization of sawtooth oscillations by the circulating energetic ions

The influence of the well-circulating energetic ions on the ideal kink instability and the m=1 tearing instabilities (collisionless and semicollisional modes) is studied. It is found that the precession of these ions can be by an important stabilizing factor, especially when the balanced tangential neutral beam injection is used and/or in the presence of fusion-produced alpha particles. (C) 2005 American Institute of Physics.