Browse by author
Lookup NU author(s): Professor Anvar ShukurovORCiD
Full text for this publication is not currently held within this repository. Alternative links are provided below where available.
Large-scale magnetic fields in spiral galaxies are strongest in spiral-shaped regions, the magnetic arms. It was recently discovered for the galaxy NGC 6946 that magnetic arms can be interlaced with the gaseous arms, rather than coinciding with them. There are indications that the magnetic and gaseous arms may cross in some other galaxies. We suggest that magnetic arms can be located away from regions of higher gas density (gaseous arms) because interstellar turbulence is stronger in the latter. We predict magnetic arms interlaced with gaseous arms in galaxies with weak dynamos, whereas the two spiral structures should overlap in galaxies with strong dynamo action; in an intermediate case, the magnetic and gaseous spiral structures overlap in the inner galaxy and are interlaced in the outer parts (as, possibly, in M51). Another plausible mechanism to produce displaced magnetic and gaseous spiral patterns results from a delay in the dynamo response to the enhancement of turbulence in the gaseous arms. This should lead to the magnetic and gaseous arms crossing at the corotation radius, as possibly observed in the galaxies IC 342 and M83. We also argue that spiral arms only weakly affect the local scaleheight of the galactic gas layer.
Author(s): Shukurov A
Publication type: Article
Publication status: Published
Journal: Monthly Notices of the Royal Astronomical Society
Year: 1998
Volume: 299
Issue: 1
Pages: L21-L24
Print publication date: 01/09/1998
ISSN (print): 0035-8711
ISSN (electronic): 1365-2966
Publisher: Wiley-Blackwell Publishing
URL: http://dx.doi.org/10.1046/j.1365-8711.1998.01958.x
DOI: 10.1046/j.1365-8711.1998.01958.x
Altmetrics provided by Altmetric
