Sub-GAM Modes in Stellarators and Tokamaks
نویسنده
چکیده
Equations describing eigenmodes with the frequencies of the order of the geodesic acoustic frequency and the electron/ion diamagnetic frequency in toroidal plasmas are derived and analyzed, a code BOAS solving them is developed. It is shown that there exist drift-sound eigenmodes and new drift-Alfvén eigenmodes. This is done by means of an analytical consideration and numerical modelling of particular discharges in the stellarator Wendelstein 7-AS. It is shown experimentally that the modes rotating in different directions can be destabilized simultaneously, which agrees with theory predictions.
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