The internal structure of toroidal Alfvén eigenmodes (TAEs) excited in ASDEX-Upgrade plasmas with ion cyclotron resonance heating (ICRH) has been measured through a high-resolution multichord soft x-ray diagnostic. The radial profiles of multiple TAEs are compared with predictions of the linear resistive magnetohydrodynamic code CASTOR and the nonperturbative gyrokinetic code LIGKA and reasonably good agreement is found. The evolution of the TAE radial profiles could be followed in time, both across sawteeth in pure ICRH discharges and in discharges with different types of transitions from L-mode to H-mode obtained with a combination of ICRH and neutral beam injection.
Investigation of high-n TAE modes excited by minority-ion cyclotron heating in JT-60U