Energetic particle physics issues for three-dimensional toroidal configurations
- ORNL
- University of Texas
- University of California
- National Institute for Fusion Science, Toki, Japan
- Max-Planck-Institute for Plasmaphysik, EURATOM-Association, Greifswald, Germany
Energetic particle physics issues are of significant interest in stellarators and rippled tokamaks. The existence and stability of shear Alfven (SA) modes in stellarators have been examined computationally through a sequence of continuum, discrete eigenmode and {delta}f calculations. Although 3D couplings greatly increase the number of available SA modes, many of these are continuum damped. By identifying the more viable modes good contact has been made with experimental observations of TAE instabilities on LHD. Sound-wave or parallel compressibility couplings can modify the Alfven spectrum at low frequencies and have been incorporated into the STELLGAP code. Regions with coupled SA-sound continua are found in frequency ranges on the HSX experiment where coherent mode activity is observed. Finally, symmetry breaking effects are studied in ITER, taking into account TF ripple, ferritic inserts and tritium blanket modules. Finite {beta} 3D equilibria are obtained, indicating that ripple is amplified within the plasma by the self-consistent currents over vacuum levels.
- Research Organization:
- Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
- Sponsoring Organization:
- USDOE Office of Science (SC)
- DOE Contract Number:
- DE-AC05-00OR22725
- OSTI ID:
- 979113
- Resource Relation:
- Conference: 22nd IAEA Fusion Energy Conference, Geneva, Switzerland, 20081013, 20081018
- Country of Publication:
- United States
- Language:
- English
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