Session GP1 - Poster Session IV.
POSTER session, Tuesday afternoon, October 30
Exhibit Hall B,
Experiments have been performed on JET to study in detail the linear stability property and the non-linear evolution of Alfvén modes in conventional and advanced tokamak scenarios with internal transport barriers. For the first time the systematic dependence of the damping rate of low-n AEs on the plasma beta, the normalized Larmor radius, the magnetic shear and safety factor, and the plasma shape was reconstructed experimentally. The AE damping rate can be accurately measured in real-time, suggesting the development of a feedback system to prevent access to unstable domains. The dynamics of quasi-periodic, upward chirping, Alfvén cascades in reversed shear equilibria is qualitatively explained in term of excitation and non-linear saturation of Energetic Particle Modes. This work has been conducted under the European Fusion Development Agreement.