Testing the Unified Model with an Infrared‐selected Sample of Seyfert Galaxies

We present a series of statistical tests done to a sample of 29 Seyfert 1 and59 Seyfert 2 galaxies selected from mostly isotropic properties, their farinfrared fluxes and warm infrared colors. Such selection criteria provide aprofound advantage over the criteria used by most investigators in the past,such as ultraviolet excess. These tests were done using ground based highresolution VLA A-configuration 3.6 cm radio and optical B and I imaging data. From the relative number of Seyfert 1's and Seyfert 2's we calculate that thetorus half opening angle is 48deg. We show that, as seen in previous papers,there is a lack of edge-on Seyfert 1 galaxies, suggesting dust and gas alongthe host galaxy disk probably play an important role in hiding some nuclei fromdirect view. We find that there is no statistically significant difference inthe distribution of host galaxy morphological types and radio luminosities ofSeyfert 1's and Seyfert 2's, suggesting that previous results showing theopposite may have been due to selection effects. The average extension of theradio emission of Seyfert 1's is smaller than that of Seyfert 2's by a factorof ~2-3, as predicted by the Unified Model. A search for galaxies around ourSeyferts allows us to put a lower and an upper limit on the possible number ofcompanions around these galaxies of 19% and 28%, respectively, with nosignificant difference in the number of companion galaxies between Seyfert 1'sand Seyfert 2's. We also show that there is no preference for the radio jets tobe aligned closer to the host galaxy disk axis in late type Seyferts, unlikeresults claimed by previous papers. These results, taken together, providestrong support for a Unified Model in which type 2 Seyferts contain a torusseen more edge-on than the torus in type 1 Seyferts.Comment: 26 pages, 3 tables and 6 figures. Accepted for publication in the Astrophysical Journa