On the theory of internal kink oscillations

Technical Report · Mon Dec 01 04:00:00 EST 1997

DOI:https://doi.org/10.2172/564315· OSTI ID:564315

Breizman, B N; Candy, J; Berk, H L ^[1]; Porcelli, F ^[1]

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1. Univ. of Texas, Austin, TX (United States). Inst. for Fusion Studies

In this paper the authors derive a time evolution equation for internal kink oscillations which is valid for both stable and unstable plasma regimes, and incorporates the nonlinear response of an energetic particle population. A linear analysis reveals a parallel between (i) the time evolution of the spatial derivative of the internal kink radial displacement and (ii) the time evolution of the perturbed particle distribution function in the field of an electrostatic wave (Landau problem). They show that diamagnetic drift effects make the asymptotic decay of internal kink perturbations in a stable plasma algebraic rather than exponential. However, under certain conditions the stable root of the dispersion relation can dominate the response of the on-axis displacement for a significant period of time. The form of the evolution equation naturally allows one to include a nonlinear, fully toroidal treatment of energetic particles into the theory of internal kink oscillations.

• Research Organization: Texas Univ., Austin, TX (United States). Inst. for Fusion Studies
• Sponsoring Organization: USDOE Office of Energy Research, Washington, DC (United States); Consiglio Nazionale delle Ricerche, Rome (Italy)
• DOE Contract Number: FG03-96ER54346
• OSTI ID: 564315
• Report Number(s): DOE/ER/54346--802; IFSR--802; ON: DE98001978
• Country of Publication: United States
• Language: English

Related Subjects

70 PLASMA PHYSICS AND FUSION TECHNOLOGY
DISPERSION RELATIONS
INTEGRAL EQUATIONS
KINK INSTABILITY
LANDAU DAMPING
MATHEMATICAL MODELS
NONLINEAR PROBLEMS
PLASMA WAVES
TIME DEPENDENCE