The magnetohydrodynamic instability of current-carrying jets

Abstract

Magnetohydrodynamic instabilities can be responsible for the formation of structures with various scales in astrophysical jets. We consider the stability properties of jets containing both the azimuthal and axial field of subthermal strength. A magnetic field with complex topology in jets is suggested by theoretical models and is consistent with recent observations. Stability is discussed by means of a linear analysis of the ideal magnetohydrodynamic equations. We argue that in azimuthal and axial magnetic fields the jet is always unstable to non-axisymmetric perturbations. Stabilization does not occur even if the strengths of these field components are comparable. If the axial field is weaker than the azimuthal one, instability occurs for perturbations with any azimuthal wave number $m$, and the growth rate reaches a saturation value for low values of $m$. If the axial field is stronger than the toroidal one, the instability shows for perturbations with relatively high $m$.

9 pages, 9 figures, to appear on A&A

References in corpus (9)

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• Astrophysical Jets and Outflows
• Stability of magnetic configurations containing the toroidal and axial fields
• Non-axisymmetric instability of axisymmetric magnetic fields
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• Parsec-scale Magnetic-Field Structures in HEAO-1 BL Lacs
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Cited by in corpus (15)

• Local Simulations of Instabilities in Relativistic Jets I: Morphology and Energetics of the Current-Driven Instability
• Stability and instability of hydromagnetic Taylor-Couette flows
• Linear stability analysis of magnetized relativistic rotating jets
• Linear stability analysis of magnetized jets: the rotating case
• Internal instabilities in magnetized jets
• On the Linear Stability of Magnetized Jets Without Current Sheets - Relativistic Case
• On the Linear Stability of Magnetized Jets Without Current Sheets: Non-Relativistic Case
• Resonance instability of axially-symmetric magnetostatic equilibria
• On the Linear Stability of Sheared and Magnetized Jets Without Current Sheets - Non-Relativistic Case
• Linear and nonlinear evolution of current-carrying highly magnetized jets
• Critical fields and growth rates of the Tayler instability as probed by a columnar gallium experiment
• Rotational suppression of the Tayler instability in stellar radiation zones
• The pinch-type instability of helical magnetic fields
• Linear Stability Analysis of Relativistic Magnetized Jets: The Minimalist Approach
• Analysis of the Instability Growth Rate During the Jet - Background Interaction in the Magnetic Field