Toroidal Alfv{acute e}n eigenmodes in TFTR deuterium{endash}tritium plasmas
- Princeton Plasma Physics Laboratory, Princeton, New Jersey08543 (United States)
Purely alpha-particle-driven toroidal Alfv{acute e}n eigenmodes (TAEs) with toroidal mode numbers n=1{endash}6 have been observed in deuterium{endash}tritium (D{endash}T) plasmas on the tokamak fusion test reactor [D. J. Grove and D. M. Meade, Nucl. Fusion {bold 25}, 1167 (1985)]. The appearance of mode activity following termination of neutral beam injection in plasmas with q(0){gt}1 is generally consistent with theoretical predictions of TAE stability [G. Y. Fu {ital et al.} Phys. Plasmas {bold 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{approximately}10{sup {minus}4} at r/a{approximately}0.3{minus}0.4 corresponds to {delta}B/B{approximately}10{sup {minus}5}, while {delta}B/B{approximately}10{sup {minus}8} is measured at the plasma edge. Enhanced alpha particle loss associated with TAE activity has not been observed. {copyright} {ital 1998 American Institute of Physics.}
- OSTI ID:
- 627767
- Report Number(s):
- CONF-971103--
- Journal Information:
- Physics of Plasmas, Journal Name: Physics of Plasmas Journal Issue: 5 Vol. 5; ISSN 1070-664X; ISSN PHPAEN
- Country of Publication:
- United States
- Language:
- English
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