Linear stability of tearing modes

Journal Article · Wed Oct 01 04:00:00 EDT 1986 · Phys. Fluids; (United States)

DOI:https://doi.org/10.1063/1.865841· OSTI ID:5137877

Cowley, S C; Kulsrud, R M; Hahm, T S

This paper examines the stability of tearing modes in a sheared slab when the width of the tearing layer is much smaller than the ion Larmor radius. The ion response is nonlocal, and the quasineutrality retains its full integral form. An expansion procedure is introduced to solve the quasineutrality equation in powers of the width of the tearing layer over the ion Larmor radius. The expansion procedure is applied to the collisionless and semicollisional tearing modes. It is found that first-order terms in the expansion are strongly stabilizing. The physics of the mode and of the stabilization are discussed. Tearing modes are observed in experiments even though the slab theory predicts stability. It is proposed that these modes grow from an equilibrium with islands at the rational surfaces. If the equilibrium islands are wider than the ion Larmor radius, the mode is unstable when ..delta..' is positive.

• Research Organization: Princeton University, Plasma Physics Laboratory, Princeton, New Jersey 08544
• OSTI ID: 5137877
• Journal Information: Phys. Fluids; (United States), Journal Name: Phys. Fluids; (United States) Vol. 29:10; ISSN PFLDA
• Country of Publication: United States
• Language: English

Related Subjects

70 PLASMA PHYSICS AND FUSION TECHNOLOGY
700107* -- Fusion Energy-- Plasma Research-- Instabilities
CHARGED PARTICLES
COLLISIONAL PLASMA
COLLISIONLESS PLASMA
INSTABILITY
IONS
LARMOR RADIUS
PLASMA
PLASMA INSTABILITY
PLASMA MACROINSTABILITIES
SHEAR
SLABS
STABILITY
TEARING INSTABILITY