High-ti Stability of Alpha Particle Driven Alfven Eigenmodes

In the present work, we analyse the two dimensional (2-D) mode structures and global stability of the Alfvkn branches, whose frequencies are close to the toroidicity induced A1fv.h continuum gap. The fully 2-D problem is solved using a two spatial-scale WKBJ formalism without employing perturbation theory in treating drive and damping terms. A code that solves the 2-D mode structures and global stability of the A1fvi.n branches is presented. Applications to a model toroidal equilibrium with ITER relevant plasma parameters are analysed. Results indicate that no unstable modes are present in the considered reference scenario.