Publication
The MHD model enables derivation and analysis of the rich structure of geodesic acoustic modes (GAMs) and zonal modes in axisymmetric magnetic confined plasmas. The modes are identifiable from a single dispersion relation as two branches of slow magnetosonic continua. The lower frequency branch can be identified as a zonal flow (ZF), which in the simplified limit of static plasmas, has vanishing magnetic component. It is shown in this contribution that axisymmetric, and lesser known non-axisymmetric, zonal modes can be derived from MHD and kinetic models. The work provides a comprehensive derivation of the GAMs and ZF continua in stationary toroidally rotating plasmas, and investigates the exact solution and structure of a generalised family of zonal modes in static equilibria.
Ali H. Sayed, Bicheng Ying, Kun Yuan, Sulaiman A S A E Alghunaim
Emanuele Mingione, Diego Alberici
Benoît Labit, Haomin Sun, Nicola Vianello, Adriano Stagni