1. Localization of MHD and fast particle modes using reflectometry in ASDEX Upgrade
- Author
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Sibylle Günter, M. Maraschek, K. Sassenberg, F. Serra, Garrard Conway, D. Borba, S. da Graca, M. E. Manso, L. Cupido, Philipp Lauber, CFN Reflectometry Group, and ASDEX Upgrade Team
- Subjects
Physics ,Tokamak ,Toroid ,Eigenfunction ,Condensed Matter Physics ,law.invention ,Computational physics ,Nuclear magnetic resonance ,Nuclear Energy and Engineering ,ASDEX Upgrade ,Physics::Plasma Physics ,law ,Phase perturbation ,Coherence (signal processing) ,Magnetohydrodynamics ,Reflectometry - Abstract
The radial structure of toroidal Alfven eigenmodes (TAEs) is of great importance for comparison with theoretical predictions. A dual-channel fast frequency hopping millimeter-wave reflectometer installed on the ASDEX Upgrade tokamak is capable of measuring density fluctuations from the plasma edge to core, allowing the radial eigenfunction of n = 4 TAE and edge MHD modes to be obtained using phase perturbation and coherence data analysis techniques. The two techniques reveal similar results, and in particular the radial structure of the n = 4 TAE is found to be in good agreement with numerical predictions from linear gyrokinetic simulations. The first results of the radial localization of Alfven cascades are also presented.
- Published
- 2007
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