Alfven eigenmodes in Helias configurations. Pt. 2

An equation for the Alfven eigenmodes (AE) derived in the work Ya. I. Kolesnichenko, V. V. Lutsenko, H. Wobig, Yu. V. Yakovenko, and O. P. Fesenyuk, Alfven eigenmodes in Helias configurations (part I), Report IPP III/261 (2000) is generalized to include effects of plasma rotation and relatively large magnitude of coupling parameters associated with strong plasma shaping. It is shown that the Doppler frequency shift is ''shared'' by Fourier harmonics that compose the gap modes. A new gap in the Alfven continuum (AC) associated with the shear of the rotation is predicted. It is demonstrated that keeping all terms with large coupling parameters considerably changes the spectrum of the AEs residing in the corresponding gap of AC. Resonances between energetic ions and AEs are analyzed. The existence of ''compound resonances'' associated with the compound structure of gap modes is predicted. An expression for the instability growth rate taking into account such a resonance is derived. Peculiarities of the gap modes and the Global Alfven Eigenmodes (GAE) are discussed. It is concluded that the GAEs can exist only in the low-frequency part of the Alfven spectrum in Wendelstein 7-AS. An explanation of the experimentally observed temporal evolution of Alfvenic activity in experiments on W7-AS is suggested. (orig.)Available from TIB Hannover: RA 71(III/271) / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekSIGLEDEGerman