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On the X-ray, optical emission line and black hole mass properties of local Seyfert galaxies
- Source :
- Astronomy and Astrophysics; August 2006, Vol. 455 Issue: 1 p173-185, 13p
- Publication Year :
- 2006
-
Abstract
- We investigate the relation between X-ray nuclear emission, optical emission line luminosities and black hole masses for a sample of 47 Seyfert galaxies. The sample, which has been selected from the Palomar optical spectroscopic survey of nearby galaxies (Ho et al. 1997a, ApJS, 112, 315), covers a wide range of nuclear powers, from $L_{2-10\,{\rm keV}}$~ 1043erg/s down to very low luminosities ($L_{2-10 \,{\rm keV}}$~ 1038erg/s). Best available data from Chandra, XMM-Newton and, in a few cases, ASCA observations have been considered. Thanks to the good spatial resolution available from these observations and a proper modeling of the various spectral components, it has been possible to obtain accurate nuclear X-ray luminosities not contaminated by off-nuclear sources and/or diffuse emission. X-ray luminosities have then been corrected taking into account the likely candidate Compton thick sources, which are a high fraction (>30%) among type 2 Seyferts in our sample. The main result of this study is that we confirm strong linear correlations between 2–10 keV, [OIII]λ5007, Hαluminosities which show the same slope as quasars and luminous Seyfert galaxies, independent of the level of nuclear activity displayed. Moreover, despite the wide range of Eddington ratios ($L/L_{\rm Edd}$) tested here (six orders of magnitude, from 0.1 down to ~10-7), no correlation is found between the X-ray or optical emission line luminosities and the black hole mass. Our results suggest that Seyfert nuclei in our sample are consistent with being a scaled-down version of more luminous AGN.
Details
- Language :
- English
- ISSN :
- 00046361 and 14320746
- Volume :
- 455
- Issue :
- 1
- Database :
- Supplemental Index
- Journal :
- Astronomy and Astrophysics
- Publication Type :
- Periodical
- Accession number :
- ejs53176253
- Full Text :
- https://doi.org/10.1051/0004-6361:20064894