Linear and nonlinear dynamics of electron fishbones
نویسندگان
چکیده
Internal kink instabilities exhibiting fishbone like behaviour have been observed in a variety of experiments where a high energy electron population, generated by strong auxiliary heating and/or current drive systems, was present. The results of global, self-consistent, non-linear hybrid MHD-Gyrokinetic simulations will be presented. Linear dynamics analysis will enlighten the effect of considering kinetic thermal ion compressibility and diamagnetic response, and kinetic thermal electrons compressibility, in addition to the energetic electron contribution. Non-linear saturation and energetic electron transport will also be addressed, making extensive use of Hamiltonian mapping techniques, discussing both centrally peaked and off-axis peaked energetic electron profiles. Centrally peaked energetic electron profiles are characterized by resonant excitation and non-linear response of deeply trapped energetic electrons. On the other side, off-axis peaked energetic electron profiles are characterized by resonant excitation and non-linear response of barely circulating energetic electrons which experience toroidal precession reversal of their motion.
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