Mode structure and continuum damping of high- n toroidal Alfven eigenmodes

Journal Article · Wed Jul 01 04:00:00 EDT 1992 · Physics of Fluids B; (United States)

DOI:https://doi.org/10.1063/1.860023· OSTI ID:7105115

Rosenbluth, M N ^[1]; Berk, H L; Van Dam, J W; Lindberg, D M ^[2]

---

1. Department of Physics, University of California, San Diego, La Jolla, California 92093 (United States)
2. Institute for Fusion Studies, The University of Texas at Austin, Austin, Texas 78712 (United States)

An asymptotic theory is described for calculating the mode structure and continuum damping of short-wavelength toroidal Alfven eigenmodes (TAE). The formalism somewhat resembles the treatment used for describing low-frequency toroidal modes with singular structure at a rational surface, where an inner solution, which for the TAE mode has toroidal coupling, is matched to an outer toroidally uncoupled solution. A three-term recursion relation among coupled poloidal harmonic amplitudes is obtained, whose solution gives the structure of the global wave function and the complex eigenfrequency, including continuum damping. Both analytic and numerical solutions are presented. The magnitude of the damping is essential for determining the thresholds for instability driven by the spatial gradients of energetic particles (e.g., neutral-beam-injected ions or fusion-product alpha particles) contained in a tokamak plasma.

• DOE Contract Number: FG05-80ET53088
• OSTI ID: 7105115
• Journal Information: Physics of Fluids B; (United States), Journal Name: Physics of Fluids B; (United States) Vol. 4:7; ISSN 0899-8221; ISSN PFBPE
• Country of Publication: United States
• Language: English

Related Subjects

70 PLASMA PHYSICS AND FUSION TECHNOLOGY
700340* -- Plasma Waves
Oscillations
& Instabilities-- (1992-)
ALFVEN WAVES
ALPHA PARTICLES
ANNULAR SPACE
ASYMPTOTIC SOLUTIONS
CHARGED PARTICLES
CLOSED CONFIGURATIONS
CLOSED PLASMA DEVICES
CONFIGURATION
DAMPING
EIGENFREQUENCY
FINITE DIFFERENCE METHOD
FLUID MECHANICS
HYDRODYNAMICS
HYDROMAGNETIC WAVES
ITERATIVE METHODS
MAGNETIC FIELD CONFIGURATIONS
MAGNETOHYDRODYNAMICS
MECHANICS
NUMERICAL SOLUTION
RECURSION RELATIONS
SPACE
THERMONUCLEAR DEVICES
TOKAMAK DEVICES
TOROIDAL CONFIGURATION