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

Xiaobo Dong·Tinggui Wang·Weimin Yuan·Hongyan Zhou·Hongguang Shan·Huiyuan Wang·Honglin Lu·Kai Zhang
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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}<10^6 \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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Xiaobo Dong, Tinggui Wang, Weimin Yuan, Hongyan Zhou, Hongguang Shan, Huiyuan Wang, Honglin Lu, Kai Zhang. 2006-12-17. Broad-line AGNs with Candidate Intermediate-mass Black holes in the Sloan Digital Sky Survey. https://arxiv.org/abs/astro-ph/0612472

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