| High-resolution radio observations of Seyfert galaxies in the extended 12-micron sample - II. The Properties of compact radio components (2001) | |||||||||||||||
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| Mon Not Astron Soc Printed April L TEX style file High resolution radio observations Seyfert galaxies the extended micron sample The properties compact radio components arXiv astro Mar Andy Thean Alan Pedlar Marek Kukula Stefi Baum and Christopher Dea Istituto Radioastronomia del CNR Via Gobetti Bologna Italy Jodrell Bank Observatory University Manchester Jodrell Bank Macclesfield Cheshire Institute for Astronomy University Edinburgh Royal Observatory Blackford Hill Edinburgh Space Telescope Science Institute San Martin Drive Baltimore Maryland USA Dec ABSTRACT discuss the properties compact nuclear radio components Seyfert galaxies from the extended AGN sample Rush Our main results can summarised follows Type and type Seyferts produce compact radio components which are indistinguishable strength and aspect indicating that their central engines are alike proposed the unification model Infrared IRAS fluxes are more closely correlated with low resolution radio fluxes than high resolution radio fluxes suggesting that they are dominated kiloparsec scale extra nuclear emission regions extra nuclear emission may stronger type Seyferts Early type Seyfert galaxies tend have stronger nuclear radio emission than late type Seyfert galaxies shaped extended emission line regions indicative ionisation cones are usually found sources with large collimated radio outflows Hidden broad lines are most likely found sources with powerful nuclear radio sources Type and type Seyferts selected their. We discuss the properties of compact nuclear radio components in Seyfert galaxies from the extended 12 µm AGN sample of Rush et al. (1993). Our main results can be summarised as follows. Type 1 and type 2 Seyferts produce compact radio components which are indistinguishable in strength and aspect, indicating that their central engines are alike as proposed by the unification model. Infrared IRAS fluxes are more closely correlated with low–resolution radio fluxes than high–resolution radio fluxes, suggesting that they are dominated by kiloparsec–scale, extra–nuclear emission regions; extra–nuclear emission may be stronger in type 2 Seyferts. Early–type Seyfert galaxies tend to have stronger nuclear radio emission than late–type Seyfert galaxies. V–shaped extended emission–line regions, indicative of ‘ionisation cones’, are usually found in sources with large, collimated radio outflows. Hidden broad lines are most likely to be found in sources with powerful nuclear radio sources. Type 1 and type 2 Seyferts selected by their IRAS 12 µm flux densities have well matched properties.. AHCT would like to acknowledge the receipt of a studentship from the Particle Physics and Astronomy Re-search Council and a visit funded by the STScI visitor program. Part of this research was supported by the European Commission, TMR Programme, Research Network Contract ERBFMRXCT96-0034 “CERES”. We have made use of NASA’s Astrophysics Data System Abstract Service, the NASA/IPAC Extragalactic database (NED), which is operated by the Jet Propulsion Laboratory, and ASURV Rev 1.1 (Lavalley, Isobe & Feigelson 1992), which implements the methods presented in Feigelson & Nelson (1985) and Isobe, Feigelson & Nelson (1986). We thank the referee, R. Antonucci, for helpful comments. | |||||||||||||||
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