A modification of the popular unification model for Seyfert galaxies is proposed, which takes into account recent observational findings on the statistical properties of both type 1 and type 2 Seyferts. In the proposed scenario, Compton–thick Seyfert 2 galaxies are those sources observed through compact, thick matter (the ‘torus’), while Compton–thin/ intermediate Seyfert galaxies are obscured ...

A modification of the popular unification model for Seyfert galaxies is proposed, which takes into account recent observational findings on the statistical properties of both type 1 and type 2 Seyferts. In the proposed scenario, Compton–thick Seyfert 2 galaxies are those sources observed through compact, thick matter (the ‘torus’), while Compton–thin/ intermediate Seyfert galaxies are obscured ...

We analyze the observed properties of nested and single stellar bar systems in disk galaxies. The 112 galaxies in our sample comprise the largest matched Seyfert vs. non-Seyfert galaxy sample of nearby galaxies with complete near-infrared or optical imaging sensitive to lengthscales ranging from tens of pc to tens of kpc. The presence of bars is deduced by fitting ellipses to isophotes in HST H...

Using recent high–resolution (<0.1”) radio observations of a large sample of Seyfert galaxies (Roy et al., 1994), we analyze the relations between their compact radio core emission and several nuclear and host galaxy properties (galaxy morphology, optical, infrared, X-ray, extended radio emissions, interaction parameters, and some emission line properties). We apply survival analysis techniques...

We present near-infrared 1.5 – 2.5 µm moderate resolution long-slit spectra of two both parallel to ionization cone or jet and perpendicular to it. The spectra are used to study the spatial extent of the line emission, integrated masses of excited H 2 and the excitation mechanisms of interstellar gas. In all three Seyfert 2 galaxies, [Fe ii] is found to be stronger than Brγ or H 2 1–0 S(1), whi...

We have derived the near-infrared structural components of a sample of Seyfert and starburst (SBN) host galaxies by fitting the images of Hunt et al. (1997) with a new two-dimensional decomposition algorithm. An analysis of the fitted parameters shows that Seyfert 1 and SBN bulges resemble normal early-type bulges in structure and color, with (J − K)cb about 0.1 mag redder than disk (J − K)cd. ...

Black hole masses in active galactic nuclei (AGN) are difficult to measure using conventional dynamical methods, but can be determined using the technique of reverberation mapping. However, it is important to verify that the results of these different methods are equivalent. This can be done indirectly, using scaling relations between the black hole and the host galaxy spheroid. For this purpos...

The large-scale ( approximately 100 kpc) environments of Seyfert galaxies are not significantly different from those of non-Seyfert galaxies. In the context of the interaction model of the formation of active galactic nuclei (AGNs), it has thus been proposed that AGNs form via "minor mergers" of large disk galaxies with smaller companions. We test this hypothesis by comparing the nuclear spectr...

We investigate the relationship between the present day optical luminosity function of galaxies and the X–ray luminosity function of Seyfert 1s to determine the fraction of galaxies which host Seyfert 1 nuclei and their Eddington ratios. The local type 1 AGN X–ray luminosity function is well reproduced if ∼ 1% of all galaxies are type 1 Seyferts which have Eddington ratios of ∼ 10−3. However, i...

This paper discusses the optical spectroscopic properties of the IRAS 1-Jy sample (f60 > 1 Jy) of ultraluminous infrared galaxies (ULIGs: Lir > 10 12 L⊙; Ho = 75 km s −1 Mpc and qo = 0). One hundred and eight of the 118 1-Jy ULIGs have been observed at ∆λ = 8.3 Å resolution over the wavelength range ∼ 4500 Å – 8900 Å. These data are combined with large, previously published sets of optical spec...