 |
 |
Astron. Astrophys. 355, 1201-1208 (2000)
Current-driven instabilities in astrophysical jets
Non linear development
T. Lery 1,2,
H. Baty 3 and
S. Appl 4
1 Dublin Institute of Advanced Studies, 5 Merrion Square, Dublin 2, Ireland
2 Department of Physics, Queen's University, Kingston, Ontario, K7L 3N6, Canada
3 Observatoire de Strasbourg, 11 rue de l'Université, 67000 Strasbourg, France
4 Institut für Angewandte Mathematik, Universität Heidelberg, Im Neuenheimer Feld 293, 69120 Heidelberg, Germany
Received 3 November 1999 / Accepted 21 January 2000
Abstract
The non linear development of instabilities driven by the presence of an electric current is investigated for magnetized jets using 3-dimensional MHD simulations. General magnetic equilibria for cold supermagnetosonic jets with constant velocity are considered in order to study the influence of the initial configuration on the non linear evolution. It is found that the current density is redistributed within the inner part of the jet radius with a characteristic time scale and an axial wavelength in agreement with the linear analysis. For equilibria having a pitch profile that increases with radius, an internal helical ribbon with a high current density is forming. It gives rise to considerable dissipation which is radially localized, and may result in heating and particle acceleration within the jet.
Key words: instabilities 
magnetic fields
ISM: jets and
outflows
galaxies:
active
galaxies: jets
Send offprint requests to: lery@cp.dias.ie
This article contains no SIMBAD objects.
Contents
- 1. Introduction
- 2. Jet equilibria and stability
- 3. The numerical model
- 4. The results
- 4.1. The ideal phase
- 4.1.1. The BFM case
- 4.1.2. The other magnetic configurations
- 4.2. The relaxation process
- 4.1. The ideal phase
- 5. Astrophysical consequences
- 6. Conclusions
- Acknowledgements
- References
© European Southern Observatory (ESO) 2000
Online publication: March 21, 2000
helpdesk.link@springer.de