OVERVIEW OF ALFVEN EIGENMODE EXPERIMENTS IN JET

Results from the first experiments to drive Alfven Eigenmodes (AEs) wi th antennas external to a tokamak plasma are presented. In ohmically h eated plasma discharges, direct experimental measurements of the dampi ng of toroidicity induced AEs (TAEs) have allowed an identification of different regimes corresponding to different dominant TAE absorption mechanisms with a wide range of damping rates, 10(-3) less than or equ al to gamma/omega less than or equal to 10(-1). In plasmas heated by i on cyclotron resonance heating, neutral beam injection heating, lower hybrid heating and high plasma current ohmic heating, a new class of w eakly damped Alfven eigenmodes, the kinetic Alfven eigenmodes, predict ed in theoretical models that include finite Larmor radius and finite parallel electric field effects, has been identified experimentally.