PPPL-3404 is available in pdf or postscript formats.

Effect of Sawtooth Oscillations on Energetic Ions

Ya. I. Kolesnichenko, V.V. Lutsenko, R.B. White, and Yu. V. Yakovenko

Date of PPPL Report: December 1999

Submitted to:Nuclear Fusion

The work summarizes results of the authors' studies on the energetic ion transport induced by sawtooth oscillations in tokamaks. The main attention is paid to description of physical mechanisms responsible for the transport. In addition to overview, the work contains new material. The new results concern the resonant interaction of the particles and the electromagnetic field of the sawtooth crash. In particular, it is discovered that the dominant harmonic of the crash (m = n = 1) can lead to stochastic motion of particles having large orbit width (potatoes). Regular motion of potatoes and quasi-stagnation particles in the presence of an n = 1 mode is studied, and their characteristic displacements associated with quick switching on/off the mode are found.