The Radio Properties of Seyfert Galaxies in the 12 Micron and CfA Samples

We report the results of 20, 6, and 2 cm VLA and 1.5 cm OVRO observations ofthe optically-selected CfA Seyfert galaxies and the bolometric-flux-limited12-Micron active galaxy sample. Every object observed was detected at 6 cm.Only 6-8% of the 12um sample Seyferts (3-4 objects) are radio-loud (and none ofthe CfA sample), as compared to 15-20% for the BQS quasars. These radio-loudobjects are compact and have flat spectra, distinguishing them from the morecommon radio-quiet objects. The 6-20 cm slopes of the Seyfert 1s and 2s are similar, with average valuesof about -0.7. Although several Seyfert 1s are significantly flatter than thisin their 6-20 and/or 1.5-6 cm slopes, there is no systematic trend for eitherSeyfert type to display upward or downward spectral curvature. Excluding the radio-loud quasars, the integrated 6 cm radio luminosity islinearly proportional to the 60um luminosity over several orders of magnitude,with on average twice the radio power of normal spirals of the samefar-infrared power. About half of the objects show extended 6 cm emission,contributing on average 33% of the total flux. Thus the luminosities of theseextended components alone are comparable to normal spirals of similar infraredluminosities. The 12um sample radio luminosity function is slightly higher than that of theCfA sample. The integrated space density of Seyfert 2s is about 2 times that ofSeyfert 1s over their common range in luminosity. In terms of the standardunified model, this ratio in space density corresponds to a typical half-angleof the torus of about 48 degress.Comment: AASTeX, 16 pages. Text and Tables 3-4 only. PostScript versions of this file, figures, and Tables 1-2, and a latex version of Tables 1-2 are available at ftp://ftp.astro.ucla.edu/pub/incoming/rush/, mget rme_*. Also get longtable.sty & fancyheadings.sty from there if you don't have them. Accepted by ApJ ~1996 July