Toroidal Alfvén Eigenmodes in TFTR Deuterium-Tritium Plasmas
- Princeton Plasma Physics Laboratory
Purely alpha-particle-driven Toroidal Alfvén Eigenmodes (TAEs) with toroidal mode numbers n=1-6 have been observed in Deuterium-Tritium (D-T) plasmas on the Tokamak Fusion Test Reactor [D.J. Grove and D.M. Meade, Nucl. Fusion 25, 1167 (1985)]. The appearance of mode activity following termination of neutral beam injection in plasmas with q(0)>1 is generally consistent with theoretical predictions of TAE stability [G.Y. Fu et al., Phys. Plasmas 3, 4036 (1996]. Internal reflectometer measurements of TAE activity is compared with theoretical calculations of the radial mode structure. Core localization of the modes to the region of reduced central magnetic shear is confirmed, however the mode structure can deviate significantly from theoretical estimates. The peak measured TAE amplitude of delta n/n~10(superscript -4) at r/a~0.3-0.4 corresponds to delta B/B~10-5, while dB/B~10(superscript -8) is measured at the plasma edge. Enhanced alpha particle loss associated with TAE activity has not been observed.
- Research Organization:
- Princeton Plasma Physics Laboratory (PPPL), Princeton, NJ
- Sponsoring Organization:
- USDOE Office of Energy Research (ER)
- DOE Contract Number:
- AC02-76CH03073
- OSTI ID:
- 4519
- Report Number(s):
- PPPL-3279; ON: DE00004519
- Country of Publication:
- United States
- Language:
- English
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