Issue |
Astron. Astrophys. Suppl. Ser.
Volume 137, Number 3, June II 1999
|
|
---|---|---|
Page(s) | 457 - 471 | |
DOI | https://doi.org/10.1051/aas:1999258 | |
Published online | 15 June 1999 |
Radio continuum morphology of southern Seyfert galaxies*
1
Istituto di Radioastronomia, CNR, Via Gobetti 101, 40129 Bologna, Italy e-mail: rmorgant@ira.bo.cnr.it
2
Department of Physics and Astronomy, Johns Hopkins University, Baltimore, MD 21218, U.S.A.
3
NRAO, 520 Edgemont Rd., Charlottesville, VA 22903, U.S.A.
4
Mount Stromlo and Siding Spring Observatories, Private Bag, Weston Creek Post Office, ACT 2611, Australia
Send offprint request to: R. Morganti
Received:
19
October
1998
Accepted:
16
April
1999
We present radio observations for 29 southern Seyfert
galaxies selected from a volume limited sample with km s-1, and
declination
. Objects with declination
were observed with the Very Large Array (VLA) at 6 cm
(4.9 GHz) and objects with
were observed with the Australia
Telescope Compact Array (ATCA) at 3.5 cm (8.6 GHz). Both the VLA and the ATCA
observations have a resolution of
. These new observations
cover more than 50% of the southern sample with all but two of the 29 objects
detected above our limit of 0.15 mJy. Combining these data with data
available from the literature gives almost 85% coverage of the southern
sample and further expands the radio observations of a distance limited sample
by 22%.
Collecting additional sources from the literature, consisting of known
Seyferts with
km s-1, we find that 38% of the sources are
unresolved at arcsecond resolution, and 34% have linear radio structure. Our
results expand upon and are consistent with earlier studies. We confirm a
correlation between the size of the radio structure and the radio luminosity.
A comparison between Seyfert types 1 and 2 finds that type 2s tend to have a
larger linear size. There is no statistically significant difference in radio
power between types 1 and 2, although all the most powerful objects appear to
be Seyfert 2's. No significant difference has been found in the spectral
indices.
Key words: radio continuum: galaxies / galaxies: Seyfert
© European Southern Observatory (ESO), 1999