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arXiv · astro-ph/0102502

Nuclear Luminosities and Radio Loudness of Seyfert Nuclei

Luis C. Ho·Chien Y. Peng
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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, when properly measured for the {\it nuclear} component, places the majority of type 1 Seyfert nuclei in the category of radio-loud AGNs, defined here as objects with R greater than or equal to 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.

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Luis C. Ho, Chien Y. Peng. 2001-02-28. Nuclear Luminosities and Radio Loudness of Seyfert Nuclei. https://doi.org/10.1086/321524

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