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Title: DISSECTING THE QUASAR MAIN SEQUENCE: INSIGHT FROM HOST GALAXY PROPERTIES

The diverse properties of broad-line quasars appear to follow a well-defined main sequence along which the optical Fe ii strength increases. It has been suggested that this sequence is mainly driven by the Eddington ratio (L/L{sub Edd}) of the black hole (BH) accretion. Shen and Ho demonstrated with quasar clustering analysis that the average BH mass decreases with increasing Fe ii strength when quasar luminosity is fixed, consistent with this suggestion. Here we perform an independent test by measuring the stellar velocity dispersion σ{sub *} (hence, the BH mass via the M–σ{sub *} relation) from decomposed host spectra in low-redshift Sloan Digital Sky Survey quasars. We found that at fixed quasar luminosity, σ{sub *} systematically decreases with increasing Fe ii strength, confirming that the Eddington ratio increases with Fe ii strength. We also found that at fixed luminosity and Fe ii strength, there is little dependence of σ{sub *} on the broad Hβ FWHM. These new results reinforce the framework that the Eddington ratio and orientation govern most of the diversity seen in broad-line quasar properties.
Authors:
 [1] ;  [2]
  1. Tsinghua Center for Astrophysics, Department of Physics, Tsinghua University, Beijing 100084 (China)
  2. Carnegie Observatories, 813 Santa Barbara Street, Pasadena, CA 91101 (United States)
Publication Date:
OSTI Identifier:
22518987
Resource Type:
Journal Article
Resource Relation:
Journal Name: Astrophysical Journal Letters; Journal Volume: 804; Journal Issue: 1; Other Information: Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; BLACK HOLES; GALAXIES; IRON; LUMINOSITY; MAIN SEQUENCE STARS; MASS; QUASARS; RED SHIFT; STAR ACCRETION; VELOCITY