Observation of multiple kinetic Alfven eigenmodes

Multiple weakly damped Alfven eigenmodes (AE) have been excited and detected by means of a dedicated active diagnostic in JET tokamak plasmas heated by ion cyclotron resonance heating, neutral beam injection heating, lower hybrid heating. and high plasma current Ohmic heating. This phenomenon is interpreted in terms of a new class of AE, the kinetic AE. predicted in theoretical models which include finite Larmor radius and toroidicity effects.