| OT03 · Damping of Kinetic Alfvén Eigenmodes in Tokamak
Plasmas
Ph. Lauber1, S. Günter1, S.D. Pinches1, A. Könies2
1Max-Planck-Institut für Plasmaphysik, EURATOM-Association, Garching, Germany
2Max-Planck Institut für Plasmaphysik, EURATOM-Association, Greifswald, Germany
Abstract: The ability to predict the stability of fast-particle-driven Alfven eigenmodes in burning
fusion plasmas requires a detailed understanding of the dissipative mechanisms that damp
these modes. In order to address this question, the linear gyro-kinetic, electromagnetic
code Ligka [1] is employed to investigate their behaviour in realistic tokamak geometry.
Ligka is based on an eigenvalue formulation and self-consistently calculates the coupling
of large-scale MHD modes to gyro-radius scale length kinetic Alfvén waves. It uses the
drift-kinetic HAGIS code [2],[3] to accurately describe the unperturbed particle orbits in
general geometry. In addition, a newly developed antenna-like version of Ligka allows for
a frequency scan, analogous to an external antenna.
With these tools the properties of the kinetically modifed TAE in or near the gap (KTAE,
radiative damping or `tunnelling' ) and its coupling to the continuum close to the edge
are numerically analysed. The results are compared with previous calculations based on
fluid and other gyro-kinetic models. Also rst linear calculations on cascade modes are
presented.
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Synopsis (pdf)