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Related papers: The Stellar Content of Active Galaxies

200 papers

The mid infrared spectra of the starbursts show the 9.7$\mu m$ silicate absorption feature and strong mid infrared emission bands centered at 6.2, 7.7, and 11.3 $\mu$m. Illustrative models of the {\it active} galaxies are presented: As the…

Astrophysics · Physics 2007-05-23 Ralf Siebenmorgen

We present near-infrared spectra for a sample of galaxies with ambiguous optical emission line ratios. These galaxies fall between starbursts and Seyferts in the usual optical diagnostic diagrams. We find a similar result with the…

Astrophysics · Physics 2009-10-31 Tanya L. Hill , Charlene A. Heisler , Ralph Sutherland , Richard W. Hunstead

We analyse star formation in the nuclei of 9 Seyfert galaxies at spatial resolutions down to 0.085arcsec, corresponding to length scales of less than 10pc in some objects. Our data were taken mostly with the near infrared adaptive optics…

Astrophysics · Physics 2009-11-13 R. Davies , F. Mueller Sanchez , R. Genzel , L. Tacconi , E. Hicks , S. Friedrich , A. Sternberg

The magnitude-limited catalog of the Southern Sky Redshift Survey (SSRS2), is used to characterize the properties of galaxies hosting Active Galactic Nuclei. Using emission-line ratios, we identify a total of 162 (3%) Seyfert galaxies out…

Astrophysics · Physics 2009-11-10 Marcio A. G. Maia , Rodolfo S. Machado , Christopher N. A. Willmer

We obtained 500-second F606W WFPC2 images of 256 of the nearest (z<0.035) Seyfert 1,Seyfert 2, and starburst galaxies. Less than 10% show tidal features or multiple nuclei. The incidence of inner starburst rings is about 10% in both classes…

Astrophysics · Physics 2009-10-30 M. A. Malkan , V. Gorjian , R. Tam

We present optical spectroscopic observations of 93 galaxies taken from the infra-red selected COLA (Compact Objects in Low Power AGN) sample. The sample spans the range of far-IR luminosities from normal galaxies to LIRGs. Of the galaxies…

We present the results of IRS low-resolution spectroscopy of 51 Seyfert galaxies, part of a large Spitzer observing program to determine the mid-to-far infrared spectral energy distributions of a well-defined sample of 87 nearby, 12…

We present the results of X-ray imaging and spectroscopic analysis of a sample of Seyfert 2 galaxies that contain starbursts, based on their optical and UV characteristics. These composite galaxies exhibit extended, soft, thermal X-ray…

Astrophysics · Physics 2009-10-31 N. A. Levenson , K. A. Weaver , T. M. Heckman

JHKL'M (1-5 micron) imaging of a sample of Seyfert (Sy) 2 galaxies is presented. We confirm that the 1-2.2 micron nuclear continuum of some Sy 2s is dominated by stellar emission, whereas the continuum emission at longer wavelengths (3-5…

Astrophysics · Physics 2009-10-31 A. Alonso-Herrero , A. C. Quillen , C. Simpson , A. Efstathiou , M. J. Ward

In a former paper (Garcia-Rissmann et al. 2005; hereafter Paper I), we have presented spectra of 64 active, 9 normal and 5 Starburst galaxies in the region around the near-IR Calcium triplet absorption lines and the [SIII]9069 line. In the…

We present optical broad band B-I colour maps of a further sample of 10 Seyfert 2 galaxies. In these bands, the contribution from emission lines to the total flux is small, and hence the images predominantly trace the continuum…

Astrophysics · Physics 2009-10-30 J. K. Kotilainen

This paper is the fourth in a series, studying the optical properties of a sample of mid-IR Warm Seyfert galaxies and of a control sample of mid-IR cold galaxies. The present paper is devoted to the analysis of the colour distributions…

Astrophysics · Physics 2007-05-23 Eleni T. Chatzichristou

We investigate the detectability of starburst signatures in the nuclear spectrum of Seyfert 2 galaxies by constructing spectral models in the wavelength range 3500-4100A, combining the spectrum of a bulge population (of age ~10Gyr) with…

To study the stellar population of local infrared galaxies, which contain star-forming galaxies, composite galaxies, LINERs, and Seyfert 2s. We also want to find whether infrared luminosity and spectral class have any effects on their…

Astrophysics · Physics 2009-03-02 X. Y. Chen , Y. C. Liang , F. Hammer , Y. H. Zhao , G. H. Zhong

An unprecedentedly large number of LINERs has been discovered in a recently completed optical spectroscopic survey of nearby galaxies, allowing several statistical properties of the host galaxies and of the line-emitting regions to be…

Astrophysics · Physics 2007-05-23 Luis C. Ho

We present a sample of 17 type 2 Seyfert galaxies which have an X-ray column density lower than 10^{22} cm^{-2}. The Compton thin nature of these sources is strongly suggested by isotropic indicators. We estimate the fraction of these…

Astrophysics · Physics 2009-11-07 Francesca Panessa , Loredana Bassani

Stellar emission and absorption lines are routinely observed in galaxies at redshifts up to 5 with spectrographs on 8-10m class telescopes. While the overall spectra are well understood and have been successfully modeled using empirical and…

Solar and Stellar Astrophysics · Physics 2013-12-10 Claus Leitherer

We present a preliminary analysis of the stellar populations in the central parsecs of a sample of 22 Seyfert 2 galaxies, based on a careful separation of nebular emission and stellar light in high-spatial resolution HST-STIS spectra. 10%…

Astrophysics · Physics 2009-11-13 Marc Sarzi , Joe Shields , Rick Pogge , Paul Martini

Using the VLT together with the near infrared instrument ISAAC, we have obtained medium spectral and high spatial resolution observations of a sample of nearby Seyfert galaxies in the H-band. This band is particularly suited for stellar…

Astrophysics · Physics 2009-11-07 C. Boisson , S. Coupe , J. G. Cuby , M. Joly , M. J. Ward

The mid-far-infrared spectral energy distributions (SEDs) of 83 active galaxies, mostly Seyfert galaxies, selected from the extended 12 micron sample are presented. The data were collected using all three instruments, IRAC, IRS, and MIPS,…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-18 J. F. Gallimore , A. Yzaguirre , J. Jakoboski , M. J. Stevenosky , D. J. Axon , S. A. Baum , C. L. Buchanan , M. Elitzur , M. Elvis , C. P. O'Dea , A. Robinson