EDP Sciences
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Volume 428, Number 2, December III 2004
Page(s) 373 - 382
Section Extragalactic astronomy
DOI http://dx.doi.org/10.1051/0004-6361:20040199

A&A 428, 373-382 (2004)
DOI: 10.1051/0004-6361:20040199

Stellar populations in Active Galactic Nuclei III

C. Boisson1, M. Joly1, D. Pelat1 and M. J. Ward2

1  LUTH, UMR 8102 du CNRS, associé à l'Université Denis Diderot, Observatoire de Paris, Section de Meudon, 92195 Meudon Cedex, France
    e-mail: catherine.boisson@obspm.fr
2  X-ray Astronomy Group, Department of Physics and Astronomy, University of Leicester, Leicester LEI 7RH, UK

(Received 4 February 2004 / Accepted 21 July 2004 )

In this paper we apply the stellar population synthesis method previously described in Boisson et al. (2000) to five more AGN.

The analysis of these new data strengthen our previous conclusions: i) homogeneity of the stellar population within a class of nuclear activity regardless of the morphological type of the host galaxy; ii) populations within the nuclear regions of LINERs and Seyfert 2s are different: LINERs have a very old metal-rich population while in the Seyfert 2s a contribution of a weak burst of star formation is observed together with the old high metallicity component; iii) in the circum-nuclar region (200 pc $\le D\le1$ kpc) of all the active galaxies in our sample, except for NGC 2992, we detect an old burst of star formation (0.2-1 Gyr),which is contrary to what is observed in normal galaxies. We note that the broad OI $\lambda$8446 Å emission line detected in the spectrum of the nucleus of NGC 2992 confirms its classification as a Seyfert 1.

Key words: galaxies: stellar content -- galaxies: active

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© ESO 2004