ASDEX Upgrade TeamCalado, R.Nabais, F.Sharapov, S. E.Schneider, P.Kazakov, Ye.Garcia-Munoz, M.Snicker, A.Ferreira, J.Coelho, R.Dreval, M.Fuertes, J.Galdon-Quiroga, J.Gonzalez-Martin, J.Karpushov, AStober, J.Tardini, G.Van Zeeland, M. A.2024-02-202024-02-202024-02-202024-01-0110.1088/1741-4326/ad0d33https://infoscience.epfl.ch/handle/20.500.14299/204592WOS:001122648300001The impact of electron cyclotron current drive (ECCD)-driven current on toroidicity-induced Alfven eigenmodes (TAEs) in experiments on the AUG tokamak is investigated numerically. The dynamical evolution of the plasma profiles and equilibria are modelled with European transport solver, while ion cyclotron resonance heating-accelerated H-minority ions exciting TAEs are assessed with the PION code. TAEs, their drive and damping are computed with the codes CASTOR and CASTOR-K. In the set of discharges analysed, two groups of TAEs are observed, differing in frequency and radial location. Experimental observations show that when counter-ECCD is applied the higher frequency group of approximately 150 kHz is suppressed, while the lower frequency modes of 125 kHz are amplified. When co-ECCD is applied, depending on the location of the ECCD current deposition layer, both groups of TAE can be suppressed. Numerical calculations of energetic particle drive and thermal plasma damping show that neither one effect could explain the variety of the experimental observations. The fine balance between the drive, sensitive to the TAE position, and the radiative and continuum damping effects could only explain the experiment if the effects are considered all together.Physical SciencesTokamaksAlfven EigenmodesEnergetic IonsEccdtext::journal::journal article::research article