2017/04/30 by Jianwei Lyu, George H. Rieke · 62 citations
Physics and Astronomy · #Active galactic nucleus #Astronomy and Astrophysical Research #Astrophysics and Star Formation Studies #Galaxies: Formation, Evolution, Phenomena #Galaxy #Infrared #Luminosity #Luminous infrared galaxy #Population #Quasar #Spectral density #astro-ph.CO #astro-ph.GA
paper · pdf · doi:10.3847/1538-4357/aa7051
published in The Astrophysical Journal 841(2), 76 (IOP Publishing) · Minor corrections to match the published version, 14 pages, 9 figures, 5 tables. The quasar intrinsic IR templates can be found at http://u.arizona.edu/~jianwei/data/AGN_temp.ascii or in the published paper
openalex created_date 2017/05/05 · arxiv created 2017/05/25 · openalex publication_date 2017/05/25 · arxiv updated 2017/05/26 · openalex updated_date 2026/08/06
Abstract The range of currently proposed active galactic nucleus (AGN) far-infrared templates results in uncertainties in retrieving host galaxy information from infrared observations and also undermines constraints on the outer part of the AGN torus. We discuss how to test and reconcile these templates. Physically, the fraction of the intrinsic AGN IR-processed luminosity compared with that from the central engine should be consistent with the dust-covering factor. In addition, besides reproducing the composite spectral energy distributions (SEDs) of quasars, a correct AGN IR template combined with an accurate library of star-forming galaxy templates should be able to reproduce the IR properties of the host galaxies, such as the luminosity-dependent SED shapes and aromatic feature strengths. We develop tests based on these expected behaviors and find that the shape of the AGN intrinsic far-IR emission drops off rapidly starting at ∼20 μ m and can be matched by an Elvis et al.-like template with a minor modification. Despite the variations in the near- to mid-IR bands, AGNs in quasars and Seyfert galaxies have remarkably similar intrinsic far-IR SEDs at λ ∼ 20–100 μ m, suggesting a similar emission character of the outermost region of the circumnuclear torus. The variations of the intrinsic AGN IR SEDs among the type-1 quasar population can be explained by the changing relative strengths of four major dust components with similar characteristic temperatures, and there is evidence for compact AGN-heated dusty structures at sub-kiloparsec scales in the far-IR.