Radio‐luminous Southern Seyfert Galaxies. I. Radio Images and Selected Optical/Near‐Infrared Spectroscopy

This is the first of two papers in which a study is made of a sample of 12southern radio-luminous Seyfert galaxies. Our aim is to investigate possiblecorrelations between radio morphology and nuclear/circumnuclear emission-lineproperties. In this paper we present radio images at 13, 6, and 3 cm taken withthe Australia Telescope Compact Array (ATCA), global far-infrared (FIR)properties for the whole sample, and optical and near-infrared (NIR)spectroscopy of an interesting subset. We find a mixture of radio morphologies,including linear, diffuse and compact sources. When the FIR colors of thegalaxies are considered there is an indication that the compact radio sourceshave warmer FIR colors than the diffuse sources, whereas the linear sourcesspan a wide range of FIR colors. There is a wide variation in radiospectral-indices, suggesting that free-free absorption is significant in somesystems, particularly IRAS 11249-2859, NGC 4507, and NGC 7213. Detailedemission-line studies are presented of 4 galaxies IC 3639, NGC 5135, NGC 3393 &IRAS 11249-2859. In IC 3639 we present evidence of vigorous, compact starformation enclosed by very extended [OI]6300 emission, suggestive of theboundary between a diffuse outflow and the surrounding ISM. In another galaxy,IC 5063, we see evidence for the possible interaction of a highly collimatedoutflow and the surrounding rotating inner disk. Of the 5 galaxies which showcompact radio emission, 4 have radio/FIR flux ratios consistent with anenergetically dominant AGN, whereas IC 4995 exhibits evidence for a verycompact starburst.Comment: 42 pages, including 7 tables, latex, 19 jpeg figures, Accepted to ApJ. Replacement updates coordintes of galaxies in Table