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arXiv · astro-ph/0108389

The fraction of galaxies that contain active nuclei and their accretion rates

M. J. Page
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Abstract

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, in such a model the X-ray luminosity function is completely dominated by AGN in E and S0 galaxies, contrary to the observed mix of Seyfert host galaxies. To obtain a plausible mix of AGN host galaxy morphologies requires that the most massive black holes in E and S0 galaxies accrete with lower Eddington ratios, or have a lower incidence of Seyfert activity, than the central black holes of later type galaxies.

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M. J. Page. 2001-08-24. The fraction of galaxies that contain active nuclei and their accretion rates. https://doi.org/10.1046/j.1365-8711.2001.04919.x

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