Optical and IR Indicators of Intrinsic AGN Luminosity

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 ┬Ám 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.
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