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Spitzer IRS spectra of a large sample of Seyfert galaxies: A Variety of infrared SEDs in the local AGN population
(Astronomical Journal, 2006-07)
We are conducting a large observing program with the Spitzer Space Telescope to determine the mid-to-far infrared spectral energy distributions of a well-defined sample of 87 nearby, 12 µm-selected Seyfert galaxies. In ...
Equatorial scattering and the structure of the broad-line region in Seyfert nuclei: Evidence for a rotating disc
(Blackwell Publishing: Monthly Notices of the Royal Astronomical Society, 2005-05)
We present detailed scattering models confirming that distinctive variations in polarization across the broad Halpha line, which are observed in a significant fraction of Seyfert 1 galaxies, can be understood in terms of ...
The supermassive black hole in the Seyfert 2 galaxy NGC 5252
(EDP Sciences: Astronomy & Astrophysics, 2005-02)
We present results from HST/STIS long-slit spectroscopy of the gas motions in the nuclear region of the Seyfert 2 galaxy NGC 5252. The observed velocity field is consistent with gas in regular rotation with superposed ...
Seyferts on the edge: Polar scattering and orientation-dependent polarization in Seyfert 1 nuclei
(Blackwell Publishing: Monthly Notices of the Royal Astronomical Society, 2004-05)
We have identified 12 Seyfert 1 galaxies that exhibit optical polarization spectra similar to those of Seyfert 2 galaxies in which polarized broad-lines are detected. We present new spectropolarimetric observations of 3 ...
Black hole masses in three Seyfert galaxies
(University of Chicago Press: Astrophysical Journal, 2003-03-01)
We analyze published reverberation mapping data for three Seyfert galaxies (NGC 3227, NGC 3516, and NGC 4593) to refine the mass estimate for the supermassive black hole in the center of each object. Treatment of the data ...
A spectropolarimetric atlas of Seyfert 1 galaxies
(Blackwell Publishing: Monthly Notices of the Royal Astronomical Society, 2002-09-27)
We present optical spectropolarimetry of the nuclei of 36 Seyfert 1 galaxies, obtained with the William Herschel and the Anglo–Australian Telescopes from 1996 to 1999. In 20 of these, the optical emission from the active ...
High-resolution radio observations of Seyfert galaxies in the extended 12-micron sample - II. The Properties of compact radio components
(Blackwell Publishing, 2001-08)
We discuss the properties of compact nuclear radio components in Seyfert galaxies from the extended 12 µm AGN sample of Rush et al. (1993). Our main results can be summarised as follows.
Type 1 and type 2 Seyferts produce ...
Supermassive black holes in active galactic nuclei. I. The Consistency of black hole masses in quiescent and active galaxies
(University of Chicago Press: Astrophysical Journal Letters, 2001-07-10)
We report the first results of a program to measure accurate stellar velocity dispersions in the bulges of the host galaxies of active galactic nuclei (AGNs) for which accurate black hole (BH) masses have been determined ...
High-resolution radio observations of Seyfert galaxies in the extended 12-micron sample - I. The Observations
(Blackwell Publishing, 2000-05)
We present 8.4 GHz VLA A–configuration observations of 87 sources from the
mid–infrared–selected AGN sample of Rush et al. (1993). These 0.25 arcsec resolution
observations allow elongated radio structures tens of parsecs ...
Gas dynamics in the barred Seyfert galaxy NGC4151 - II. High resolution HI study
(Blackwell Publishing: Monthly Notices of the Royal Astronomical Society, 1999-04)
We present sensitive, high angular resolution (6′′ × 5′′) λ21-cm observations of the neutral hydrogen in the nearby barred Seyfert galaxy, NGC4151. These HI observations, obtained using the VLA in B-configuration, are the ...