Alpha particle destabilization of the toroidicity-induced Alfven eigenmodes

Journal Article · Sun Sep 01 00:00:00 EDT 1991 · Physics of Fluids B; (United States)

DOI:https://doi.org/10.1063/1.859618· OSTI ID:5370513

Cheng, C Z ^[1]

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1. Plasma Physics Laboratory, Princeton University, Princeton, New Jersey (USA)

The high-frequency, low mode number toroidicity-induced Alfven eigenmodes (TAE) (Phys. Fluids {bold 29}, 3695 (1986)) are shown to be driven unstable by the circulating and/or trapped {alpha} particles through the wave--particle resonances. Satisfying the resonance condition requires that the {alpha}-particle birth speed {ital v}{sub {alpha}}{ge}{ital v}{sub A}/2{vert bar}{ital m}{minus}{ital nq}{vert bar}, where {ital v}{sub A} is the Alfven speed, {ital m} is the poloidal mode number, and {ital n} is the toroidal mode number. To destabilize TAE modes, the inverse Landau damping associated with the {alpha}-particle pressure gradient free energy must overcome the velocity space Landau damping due to both the {alpha} particles and the core electrons and ions. The growth rate was studied analytically with a perturbative formula derived from the quadratic dispersion relation, and numerically with the aid of the NOVAcode. Stability criteria in terms of the {alpha}-particle beta {beta}{sub {alpha}}, {alpha}-particle pressure parameter ({omega}{sub *}/{omega}{sub A}) ({omega}{sub *} is the {alpha}-particle diamagnetic drift frequency), and ({ital v}{sub {alpha}}/{ital v}{sub A}) parameters will be presented for the Tokamak Fusion Test Reactor (TFTR) ({ital Proceedings} {ital of} {ital the} {ital Thirteenth} {ital International} {ital Conference} {ital on} {ital Plasma} {ital Physics} {ital and} {ital Controlled} {ital Nuclear} {ital Fusion} {ital Research}, Crystal City, VA, 1990 (International Atomic Energy Agency, Vienna, in press)), Compact Ignition Tokamak (CIT) (Phys. Scr. {bold T16}, 89 (1987)), and the International Thermonuclear Experimental Reactor (ITER) (ITER Documentation Series, No. 21 (International Atomic Energy Agency, Vienna, 1991)).

• DOE Contract Number: AC02-76CH03073
• OSTI ID: 5370513
• Journal Information: Physics of Fluids B; (United States), Journal Name: Physics of Fluids B; (United States) Vol. 3:9; ISSN 0899-8221; ISSN PFBPE
• Country of Publication: United States
• Language: English

Related Subjects

70 PLASMA PHYSICS AND FUSION TECHNOLOGY
700107 -- Fusion Energy-- Plasma Research-- Instabilities
700108* -- Fusion Energy-- Plasma Research-- Wave Phenomena
ALFVEN WAVES
ALPHA PARTICLES
ANALYTICAL SOLUTION
ANNULAR SPACE
CHARGED PARTICLES
CLOSED CONFIGURATIONS
CLOSED PLASMA DEVICES
COMPACT IGNITION TOKAMAK
CONFIGURATION
DAMPING
DIAMAGNETISM
EIGENVALUES
FLUCTUATIONS
HYDROMAGNETIC WAVES
INSTABILITY GROWTH RATES
LANDAU DAMPING
MAGNETIC FIELD CONFIGURATIONS
MAGNETISM
NUCLEAR REACTIONS
NUCLEOSYNTHESIS
PLASMA
PRESSURE GRADIENTS
RESONANCE
SPACE
STABILITY
SYNTHESIS
THERMONUCLEAR DEVICES
THERMONUCLEAR REACTIONS
THERMONUCLEAR REACTORS
TOKAMAK DEVICES
TOKAMAK TYPE REACTORS
TOROIDAL CONFIGURATION
TRAJECTORIES
VARIATIONS