High-order geodesic coupling of shear-Alfvén and acoustic continua in tokamaks
High-order geodesic coupling of shear-Alfvén and acoustic continua in tokamaks
High-order plasma shaping (mainly elongation and shift, as opposed to low-order toroidicity) is shown, under certain conditions, to open gaps in the coupled shear-Alfvén and acoustic continua at frequencies significantly above the values predicted by previous theories. Global eigenmodes in these gaps, which lie between those of geodesic acoustic modes …