M. Dumke & M. Krause
Max-Planck-Institut für Radioastronomie, Auf dem Hügel
69, D-53121 Bonn, Germany
Received 23 June 1997 / Accepted 14 July 1997
Published in: Breitschwerdt D., Freyberg M.J., Trümper J. (eds.), Proc. IAU Coll. 166 "The Local Bubble and Beyond", Lecture Notes in Physics 506, 555. Springer-Verlag Heidelberg (1998)
Abstract:
We have observed a small sample of edge-on galaxies in total and linearly polarized radio continuum emission at 6.2 cm, using the Effelsberg 100 m telescope. The resulting maps were combined with available VLA data in order to obtain high-sensitivity radio images which have a sufficient angular resolution and do not suffer from the so-called missing-spacing problem.
From an analysis of these images (together with 2.8 cm and 20 cm data) we get the following results: 1. The radio emission perpendicular to the plane can be described by a two-component exponential distribution with scale-heights of ~ 300 pc and ~ 1.8 kpc, independently of the star forming activity and interaction state. 2. In the disk of the non-interacting galaxies of our sample the thermal fraction of the emission seem to be higher than usually deduced from observations of face-on galaxies. 3. The fractional polarization p increases with increasing galactic height, reaches a maximum at h ~ 1 - 3 kpc, and decreases again. In general p is lower in actively star forming galaxies.
Keywords: galaxies: individual: NGC891, NGC3628, NGC4565 - galaxies: ISM - radio continuum: galaxies - polarization
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