Origin, Structure and Stability of Astrophysical MHD Jets

The following sections are included:

• Introduction

• Generalities on astrophysical jets

  • Accretion

    • Active Galactic Nuclei

    • Young stellar objects

  • Magnetic fields in jets

  • Relativistic vs non-relativistic jets in AGNs

• Origin of jets

  • Central object

  • Disk/central-object interaction region

  • Disk

• MHD jet structure

  • Jet launching and magnetic surface opening

  • Current structure, and jet acceleration and collimation

• Stability of MHD jets

  • Global disk-jet stability and stationarity

  • Motion driving: the Kelvin-Helmholtz instability

  • Magnetic driving: the current and pressure instabilities

    • Current-driven instabilities

    • Pressure-driven instabilities

• Summary and open issues

• A brief compendium of relevant astrophysical facts

  • Mostly AGNs

  • Origin of magnetic fields

  • On the MHD approximation in astrophysics

• MHD axisymmetric steady-state equations

  • General form

  • Ideal MHD form

• The Kelvin-Helmholtz instability of a single vortex sheet layer

• MHD stability and the energy principle

• Pressure-driven instabilities asymptotic limit

• Acknowledgments

• References