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Title: The Accretion History of AGN: The Spectral Energy Distributions of X-Ray-luminous Active Galactic Nuclei

Spectral energy distributions (SEDs) from X-ray to far-infrared (FIR) wavelengths are presented for a sample of 1246 X-ray-luminous active galactic nuclei (AGNs;L0.5–10 keV> 1043erg s−1), withzspec< 1.2, selected from Stripe 82X, COSMOS, and GOODS-N/S. The rest-frame SEDs show a wide spread (∼2.5 dex) in the relative strengths of broad continuum features at X-ray, ultraviolet (UV), mid-infrared (MIR), and FIR wavelengths. A linear correlation (log–log slope of 0.7 ± 0.04) is found betweenLMIRandLX. There is significant scatter in the relation between theLUVandLXowing to heavy obscuration; however, the most luminous and unobscured AGNs show a linear correlation (log–log slope of 0.8 ± 0.06) in the relation above this scatter. The relation betweenLFIRandLXis predominantly flat, but with decreasing dispersion atLX> 1044erg s−1. The ratio between the “galaxy-subtracted” bolometric luminosity and the intrinsicLXincreases from a factor of ∼10 to 70 from logLbol/(erg s−1) = 44.5 to 46.5. Characteristic SED shapes have been determined by grouping AGNs based on relative strengths of the UV and MIR emission. The averageL1μmis constant for the majority of these SED shapes, while AGNs with the strongest UV and MIR emission have elevatedL1μm, consistent with the AGN emission dominating their SEDs at optical and near-infrared wavelengths. A strong correlation is found between the SED shape and both theLXandLbol, such thatLbol/LX= 20.4 ± 1.8, independent of the SED shape. This is consistent with an evolutionary scenario of increasingLbolwith decreasing obscuration as the AGN blows away circumnuclear gas.

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Author(s) / Creator(s):
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DOI PREFIX: 10.3847
Date Published:
Journal Name:
The Astrophysical Journal
Medium: X Size: Article No. 19
Article No. 19
Sponsoring Org:
National Science Foundation
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