Kink instabilities in jets from rotating magnetic fields
Max-Planck-Institut für Astrophysik, Karl-Schwarzschild-Str. 1, 85741 Garching, Germany e-mail: firstname.lastname@example.org
Accepted: 15 September 2008
We have performed 2.5D and 3D simulations of conical jets driven by the rotation of an ordered, large-scale magnetic field in a stratified atmosphere. The simulations cover about three orders of magnitude in distance to capture the centrifugal acceleration as well as the evolution past the Alfvénsurface. We find that the jets develop kink instabilities, the characteristics of which depend on the velocity profile imposed at the base of the flow. The instabilities are especially pronounced with a rigid rotation profile, which induces a shearless magnetic field. The jet's expansion appears to be limiting the growth of Alfvénmode instabilities.
Key words: magnetohydrodynamics (MHD) / instabilities / ISM: jets and outflows / galaxies: quasars: general / gamma rays: bursts
© ESO, 2008