Nearby Seyfert galaxies

Abstract

The paper contains preliminary results from a photographic study of 30 nearby Seyfert galaxies (V<SUB>R</SUB> less than 5000 km/s). The appearance of these well-resolved objects suggests that the morphology of both Seyfert type 1 and type 2 galaxies is characterized by a three-step distribution in the radial surface brightness of the disk. Superposed on this three-step distribution is a continuum of spiral-like patterns, ranging from sharp, distinct arms to diffuse, amorphous segments. An interpretation of this morphology is presented which suggests that the nuclear activity in these objects is fed by gas from the disk and that the disturbed amorphous structure found in some Seyferts is the end product of this feeding. Analysis of the relation between the inclination of the disk and the H-beta FWZI for type 1 Seyferts in this sample suggests that these may be correlated. However, an alternative interpretation of this relation is that larger values of FWZI are associated with more amorphous type 1 Seyferts. The space density in the sample of Seyfert galaxies discussed here appears to be greater than that previously ascribed to these objects.