The Fueling of Nuclear Activity: II. The Bar Properties of Seyfert and Normal Galaxies

We use a recent near-infrared imaging survey of samples of Seyfert and normal galaxies to study the role of bars in the fueling of nuclear activity. The active galaxy sample includes Seyfert galaxies in the Revised Shapely-Ames (RSA) and Sandage & Tammann’s (1987) extension to this catalog. The normal galaxies were selected to match the Seyfert sample in Hubble type, redshift, inclination and blue luminosity. All the galaxies in both samples classified as barred in the RSA catalog are also barred in the near-infrared. In addition, ∼ 55% of the galaxies classified as non-barred in the RSA show evidence for bars at 2.1 μm. Overall, ∼ 70% of the galaxies observed show evidence for bar structures. The incidence of bars in the Seyfert and normal galaxies is similar, suggesting Seyfert nuclei do not occur preferentially in barred systems. Furthermore, a slightly higher percentage of normal galaxies have multiple-bar structures. A significant percentage of the Seyfert galaxies in our sample show no evidence for the presence of a bar even in the near-infrared. This suggests that either large-scale kiloparsec bars are not a universal fueling mechanism in Seyfert galaxies or that the bars in the non-barred Seyferts were recently destroyed, possibly by the formation of the central black hole. Visiting Astronomer, Kitt Peak National Observatory, National Optical Astronomy Observatories, operated by the Association of Universities for Research in Astronomy, Inc., under contract with the National Science Foundation. [email protected] [email protected]