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arXiv · 1404.6374

Bi-directional Alfv\'en Cyclotron Instabilities in the Mega-Amp Spherical Tokamak

S. E. Sharapov·M. K. Lilley·R. Akers·N. Ben Ayed·M. Cecconello·J. W. C. Cook·G. Cunningham·E. Verwichte·the MAST Tea
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Abstract

Alfv\'en cyclotron instabilities excited by velocity gradients of energetic beam ions were investigated in MAST experiments with super-Alfv\'enic NBI over a wide range of toroidal magnetic fields from ~0.34 T to ~0.585 T. In MAST discharges with high magnetic field, a discrete spectrum of modes in the sub-cyclotron frequency range is excited toroidally propagating counter to the beam and plasma current (toroidal mode numbers n < 0).

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S. E. Sharapov, M. K. Lilley, R. Akers, N. Ben Ayed, M. Cecconello, J. W. C. Cook, G. Cunningham, E. Verwichte, the MAST Tea. 2014-04-25. Bi-directional Alfv\'en Cyclotron Instabilities in the Mega-Amp Spherical Tokamak. https://doi.org/10.1063/1.4891322

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