Helicity proxy for edge-on galaxies
Brandenburg, Axel KTH Royal Institute of Technology and Stockholm University|Stockholm University|University of Colorado|Carnegie Mellon University
Furuya, Ray S. Tokushima University Tokushima University Educator and Researcher Directory KAKEN Search Researchers
dynamo –MHD– polarization – turbulence – galaxies
NGC 891 – galaxies
We study the prospects of detecting magnetic helicity in galaxies by observing the dust polarization of the edge-on galaxy NGC 891. Our numerical results of mean-field dynamo calculations show that there should be a large-scale component of the rotationally invariant parity-odd B polarization that we predict to be negative in the first and third quadrants, and positive in the second and fourth quadrants. The large-scale parity-even E polarization is predicted to be negative near the axis and positive further away in the outskirts. These properties are shown to be mostly a consequence of the magnetic field being azimuthal and the polarized intensity being maximum at the centre of the galaxy and are not a signature of magnetic helicity.
Monthly Notices of the Royal Astronomical Society
Oxford University Press|The Royal Astronomical Society
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mnras_496_4_4749.pdf 939 KB
Liberal Arts and Sciences