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arXiv · 0806.1787

The Origin and Evolution of \civ Baldwin Effect in QSOs from the Sloan Digital Sky Survey

Yan Xu·Wei-Hao Bian·Qi-Rong Yuan·Ke-Liang Huang
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Abstract

Using a large sample of 26623 quasars with redshifts in the range $1.5 \le z\le 5.1$ with \civ $λ$1549 Åemission line in Fifth Data Release of the Sloan Digital Sky Survey (SDSS), we investigate the cosmological evolution of the Baldwin Effect, i.e. the relation between the equivalent width (EW) of the \civ emission line and continuum luminosity. We confirm the earlier result that there exists a strong correlation between the \civ EW and the continuum luminosity, and we find that, up to $z\approx 5$, the slope of the Baldwin Effect seems to have no effect of cosmological evolution. A sub-sample of 13960 quasars with broad \civ $λ$1549 Åemission line from SDSS is used to explore the origin of the Baldwin Effect. We find that \civ EW have a strong correlation with the mass of supermassive black hole (SMBH), and a weak correlation with the Eddington ratio, $\lb/\ledd$. This suggests that the SMBH mass is probably the primary drive for the Baldwin Effect.

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Yan Xu, Wei-Hao Bian, Qi-Rong Yuan, Ke-Liang Huang. 2008-06-11. The Origin and Evolution of \civ Baldwin Effect in QSOs from the Sloan Digital Sky Survey. https://doi.org/10.1111/j.1365-2966.2008.13545.x

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