Broad-line AGNs with Candidate Intermediate-mass Black holes in the Sloan Digital Sky Survey

2006/12/17 by Xiaobo Dong, Xiao-Bo Dong, Dong, Xiaobo +16
Physics and Astronomy · #Astronomy and Astrophysical Research #Astrophysics (astro-ph) #FOS: Physical sciences #Galaxies: Formation, Evolution, Phenomena #Gamma-ray bursts and supernovae #astro-ph

paper · pdf · doi:10.48550/arxiv.astro-ph/0612472

Conference proceedings to appear in "The Central Engine of Active Galactic Nuclei", ed. L. C. Ho and J.-M. Wang (San Francisco: ASP)

arxiv created 2006/12/17 · openalex publication_date 2006/12/17 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28

Abstract

We have conducted a systematic search of AGNs with IMBHs from the SDSS DR4. As results we found 245 candidates of broad-line AGN with M_BH<10⁶ \Msun estimated from the luminosity and width of the broad Halpha component. Compared to the pioneer Greene & Ho (2004) sample of 19 IMBH AGNs, our sample has improved in covering a larger range of the Eddington ratio, as well as black hole mass and redshift, taking the advantage of our AGN-galaxy spectral decomposition algorithm. Among these, thirty-six have L_bol/L_Edd < 0.1, hinting that a significant fraction of IMBHs might exist with weak or no nuclear activity.

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