Hostname: page-component-78c5997874-s2hrs Total loading time: 0 Render date: 2024-11-13T07:16:01.978Z Has data issue: false hasContentIssue false

Magnetic Field Generation by Galactic Winds

Published online by Cambridge University Press:  19 July 2016

S.J. Spencer
Affiliation:
School of Physics, The University of Sydney, N.S.W. 2006, Australia
L.E. Cram
Affiliation:
School of Physics, The University of Sydney, N.S.W. 2006, Australia

Abstract

Core share and HTML view are not available for this content. However, as you have access to this content, a full PDF is available via the ‘Save PDF’ action button.

A new mechanism is presented for the local amplification and possible global dynamo maintenance of non-axisymmetric large-scale magnetic fields in disk galaxies. Shear in a galactic wind or large-scale flow of ionised gas with components axial and radial to the disk plane may regenerate large-scale magnetic fields.

Numerical results are presented from kinematic mathematical models based on a local (thin disk) approximation and an exact three-dimensional formulation. The one-dimensional thin-disk model illustrates the possibility of exponential amplification and the resulting local axial spatial structure of large-scale galactic magnetic fields. Three-dimensional results support the possibility of global wind dynamo action.

Type
8. Magnetic Fields in Galaxies: Dynamo Theory
Copyright
Copyright © Kluwer 1993 

References

Beck, R.: 1991, in ‘The Interstellar Disk-Halo Connection in Galaxies’, IAU Symposium 144, ed. Bloemen, J.B.G.M. (Dordrecht:Kluwer),267.Google Scholar
Cowling, T.G.: 1981, ARA&A 19,115.Google Scholar
Dahlem, M.: 1990, ‘Disk-halo Interactions in the Spiral Galaxies NGC 1808 and NGC 891’, PhD. Thesis (Bonn: Rheinischen Friedrich-Wilhelms Universität)Google Scholar
Ekers, R.D. & Sancisi, R.: 1977, A&A 54,973.Google Scholar
Elstner, D., Meinel, R. & Rüdiger, G.: 1990, GeoApFlDyn 50,85.Google Scholar
Evans, C.R. & Hawley, J.F.: 1988, ApJ 332,659.Google Scholar
Fujimoto, M. & Sawa, T.: 1987, Pub. Astr. Soc. Japan 39, 375.Google Scholar
Hummel, E., Lesch, H., Wielebinski, R. & Schlickeiser, R.: 1988, A&A 197, L29.Google Scholar
Hummel, E., Sancisi, R. & Ekers, R.D.: 1984, A&A 133, 1.Google Scholar
Hummel, E. & Dahlem, M.: 1990, in ‘Galactic and Intergalactic Magnetic Fields’, IAU Symposium 140, eds. Beck, R., Kronberg, P.P., Wielebinski, R. (Dordrecht:Kluwer),219.Google Scholar
Lerche, I. & Schlickeiser, R.: 1981, Ap. Letters 22,31.Google Scholar
Moffatt, H.K.: 1978, ‘Magnetic Field Generation in Electrically Conducting Fluids’ (Cambridge:Cambridge University)Google Scholar
Parker, E.N.: 1971, ApJ 163,255.Google Scholar
Parker, E.N.: 1979, ‘Cosmical Magnetic Fields’ (Oxford:Clarendon)Google Scholar
Ruzmaikin, A.A., Shukurov, A.M. & Sokoloff, D.D.: 1988, ‘Magnetic Fields in Spiral Galaxies’ (Dordrecht:Kluwer)Google Scholar
Sofue, Y., Fujimoto, M. & Wielebinski, R.: 1986, ARA&A 24,459.Google Scholar
Spencer, S.J. & Cram, L.E.: 1992, ApJ 400, in press.Google Scholar
Sukumar, S. & Velusamy, T.: 1985, MNRAS 212,367.Google Scholar
Zeldovich, Y.B., Ruzmaikin, A.A. & Sokoloff, D.D.: 1983, ‘Magnetic Fields in Astrophysics’ (New York:Gordon and Breach)Google Scholar