Nuclear Luminosities and Radio Loudness of Seyfert Nuclei
Open Access
- 10 July 2001
- journal article
- research article
- Published by American Astronomical Society in The Astrophysical Journal
- Vol. 555 (2) , 650-662
- https://doi.org/10.1086/321524
Abstract
Historically, Seyfert nuclei have been considered to be radio-quiet active galactic nuclei (AGNs). We question this widely held assumption by showing that the distribution of the radio-to-optical luminosity ratio, R ≡ Lν(6 cm)/Lν(B), when properly measured for the nuclear component, places the majority of type 1 Seyfert nuclei in the category of radio-loud AGNs, defined here as objects with R ≥ 10. This result is further strengthened by strong correlations found between radio power and optical continuum and emission-line luminosities, as has been established previously for more powerful AGNs. We also present a new calibration of the relation between optical continuum and Balmer emission-line luminosities valid in the regime of low-luminosity AGNs.Keywords
All Related Versions
This publication has 106 references indexed in Scilit:
- A Study of Quasar Radio Emission from the VLA FIRST SurveyThe Astronomical Journal, 1999
- The radio properties of radio-quiet quasarsMonthly Notices of the Royal Astronomical Society, 1998
- Properties of Host Galaxies of Powerful Radio SourcesThe Astrophysical Journal, 1996
- Compact Radio Cores and Nuclear Activity in Seyfert GalaxiesThe Astrophysical Journal, 1996
- Seyfert Galaxies. IV. Nuclear Profiles of Markarian Seyfert Galaxies from Hubble Space Telescope ImagesThe Astrophysical Journal, 1996
- Virial and jet-induced velocities in Seyfert Galaxies. II - Galaxy rotation as virial parameter. III - Galaxy luminosity as virial parameterThe Astrophysical Journal, 1992
- Statistical methods for astronomical data with upper limits. I - Univariate distributionsThe Astrophysical Journal, 1985
- Radio structures of Seyfert galaxies. V - A flux-limited sample of Markarian galaxiesThe Astrophysical Journal, 1984
- Multicolor surface photometry of Markarian Seyfert galaxiesThe Astrophysical Journal, 1983
- MRK 744 and MRK 1066 - Two Seyfert galaxies with strong absorption-line spectraThe Astrophysical Journal, 1983