Type |
Conference Paper |
Names |
Stephanie M. LaMassa, T. Heckman, A. Ptak, A. Hornschemeier, L. Martins, P. Sonnentrucker, C. Tremonti |
Proceedings Title |
Bulletin of the American Astronomical Society |
Conference Name |
American Astronomical Society, AAS Meeting #215, #411.16 |
Volume |
42 |
Pages |
242 |
Date |
January 1, 2010 |
URL |
http://adsabs.harvard.edu/abs/2010AAS...21541116L |
Library Catalog |
NASA ADS |
Abstract |
Seyfert galaxies, the major type of Active Galactic Nuclei (AGN) in the
local universe, are powered by accretion onto a central supermassive
black hole and are surrounded by an obscuring torus of dust and gas. In
Type 2 Seyferts (Sy2s), this torus is oriented along the line of sight
of the observer. Though the accretion disk is therefore blocked from
view, the strength of the AGN's ionizing continuum can still be
inferred. Isotropic indicators of intrinsic AGN luminosity include the
flux of emission lines formed in the narrow line region, such as the
[OIII] 5007 Angstrom line and the [OIV] 25.89 µm line. Such lines
are excited by the continuum of the accretion disk and are unaffected by
the torus obscuration. The mid-infrared continuum luminosity from the
torus is another diagnostic of AGN luminosity as the dust is heated by
the central engine. Here we compare the isotropic AGN luminosity
indicators of two homogeneous samples of type 2 Seyfert galaxies. One
sample was selected from the Sloan Digital Sky Survey based on high
[OIII] flux values and the other consists of Sy2s selected on the basis
of their mid-IR continuum flux.
This work is funded by NASA grant number NNX07AQ36G. |