PPPL-3543 is available in <a href="PPPL-3543.pdf">pdf</a> or 
<a href="PPPL-3543.ps">postscript</a> formats.

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<b>Transport of Energetic Ions during Relaxation Oscillations in Plasmas of Spherical Tori</b>
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<b>Authors:</b> Ya.I. Kolesnichenko, V.V. Lutsenko, R.B. White, and Yu.V. Yakovenko

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<b>Date of PPPL Report:</b> February 2001
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<b>Submitted to:</b> Physical Review Letters
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It is shown that the confinement of trapped energetic ions in spherical tokamaks during MHD events, such as sawtooth oscillations and internal reconnection events (IRE), essentially depends on beta (beta is the ratio of plasma pressure to the magnetic field pressure). Namely, when beta is high, the energetic ions are expelled from the plasma core, whereas they are only weakly influenced by the MHD activity at relatively low beta. Because of this, moderate rather than the highest possible beta may be preferable in spherical tokamaks.




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