2005/03/23 by Chris Simpson · 3 citations
Physics and Astronomy · #Active galactic nucleus #Astronomy #Astrophysical Phenomena and Observations #Astrophysics #Galaxies: Formation, Evolution, Phenomena #Galaxy #Gamma-ray bursts and supernovae #Geometry #Line (geometry) #Luminosity #Luminosity function #Luminous infrared galaxy #Physics #Sky #Torus #astro-ph
paper · pdf · doi:10.1111/j.1365-2966.2005.09043.x
published as Mon.Not.Roy.Astron.Soc. 360 (2005) 565-572 · 8 pages, accepted for publication by MNRAS
arxiv created 2005/03/23 · openalex publication_date 2005/06/21 · arxiv updated 2009/12/01 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/05
Using a complete, magnitude-limited sample of active galaxies from the Sloan Digital Sky Survey, we show that the fraction of broad-line (type 1) active galactic nuclei (AGNs) increases with luminosity of the isotropically emitted [Oiii] narrow emission line. Our results are quantitatively in agreement with, and far less uncertain than, similar trends found from studies of X-ray and radio-selected active galaxies. While the correlation between broad-line fraction and luminosity is qualitatively consistent with the receding torus model, its slope is shallower and we therefore propose a modification to this model where the height of the torus increases slowly with AGN luminosity. We demonstrate that the faint-end slope of the AGN luminosity function steepens significantly when a correction for ‘missing’ type 2 objects is made, and that this can substantially affect the overall AGN luminosity density extrapolated from samples of more luminous objects.