Contained Modes In Mirrors With Sheared Rotation
Authors: Abraham J. Fetterman and Nathaniel J. Fisch
Abstract:
In mirrors with E × B rotation, a fixed azimuthal perturbation in the lab frame can appear as a wave in the rotating frame. If the rotation frequency varies with radius, the plasma-frame wave frequency will also vary radially due to the Doppler shift. A wave that propagates in the high rotation plasma region might therefore be evanescent at the plasma edge. This can lead to radially localized Alfven eigenmodes with high azimuthal mode numbers. Contained Alfven modes are found both for peaked and non-peaked rotation profiles. These modes might be useful for alpha channeling or ion heating, as the high azimuthal wave number allows the plasma wave frequency in the rotating frame to exceed the ion cyclotron frequency.
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Submitted to: Physics of Plasmas (October 2010)
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Download PPPL-4569 (pdf 663 KB 7 pp)
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