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Title: Empirical links between XRB and AGN accretion using the complete z < 0.4 spectroscopic CSC/SDSS catalog

Striking similarities have been seen between accretion signatures of Galactic X-ray binary (XRB) systems and active galactic nuclei (AGNs). XRB spectral states show a V-shaped correlation between X-ray spectral hardness and Eddington ratio as they vary, and some AGN samples reveal a similar trend, implying analogous processes at vastly larger masses and timescales. To further investigate the analogies, we have matched 617 sources from the Chandra Source Catalog to Sloan Digital Sky Survey spectroscopy, and uniformly measured both X-ray and optical spectral characteristics across a broad range of AGN and galaxy types. We provide useful tabulations of X-ray spectral slope for broad- and narrow-line AGNs, star-forming and passive galaxies, and composite systems, also updating relationships between optical (Hα and [O III]) line emission and X-ray luminosity. We further fit broadband spectral energy distributions with a variety of templates to estimate bolometric luminosity. Our results confirm a significant trend in AGNs between X-ray spectral hardness and Eddington ratio expressed in X-ray luminosity, albeit with significant dispersion. The trend is not significant when expressed in the full bolometric or template-estimated AGN luminosity. We also confirm a relationship between the X-ray/optical spectral slope α{sub ox} and Eddington ratio, but it may not followmore » the trend predicted by analogy with XRB accretion states.« less
Authors:
 [1] ; ; ; ;  [2] ;  [3] ;  [4] ;  [5] ;  [6] ;  [7] ;  [8]
  1. EADS Astrium, Gunnels Wood Road, Stevenage, Hertfordshire SG1 2AS (United Kingdom)
  2. Harvard-Smithsonian Center for Astrophysics, Cambridge, MA 02138 (United States)
  3. Department of Physics and Astronomy, James Madison University, PHCH, Harrisonburg, VA 22807 (United States)
  4. Center for Astrophysics, Science and Technology Research Institute, University of Hertfordshire, Hatfield AL10 9AB (United Kingdom)
  5. Astrophysics Group, Imperial College London, London SW7 2AZ (United Kingdom)
  6. Center for Astrophysics, University of Science and Technology of China, Hefei 230026 (China)
  7. Center for Interdisciplinary Exploration and Research in Astrophysics, Northwestern University, 2145 Sheridan Road, Evanston, IL 60208 (United States)
  8. Department of Physics, Broida Hall, University of California, Santa Barbara, CA 93107 (United States)
Publication Date:
OSTI Identifier:
22341916
Resource Type:
Journal Article
Resource Relation:
Journal Name: Astrophysical Journal; Journal Volume: 778; Journal Issue: 2; Other Information: Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; BINARY STARS; BLACK HOLES; BOLOMETERS; CATALOGS; CORRELATIONS; COSMIC X-RAY SOURCES; DISPERSIONS; EMISSION; ENERGY SPECTRA; GALAXY NUCLEI; HARDNESS; LUMINOSITY; MASS; QUASARS; SKY; SPECTROSCOPY; STARS; X RADIATION; X-RAY GALAXIES