On strong correlation between shifted velocity and line width of broad blue-shifted [OIII] components in quasars

Zhang XueGuang

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arXiv · 2101.02465

On strong correlation between shifted velocity and line width of broad blue-shifted [OIII] components in quasars

Zhang XueGuang

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Abstract

In this manuscript, we report strong linear correlation between shifted velocity and line width of the broad blue-shifted [OIII] components in SDSS quasars. Broad blue-shifted [OIII] components are commonly treated as indicators of outflows related to central engine, however, it is still an open question whether the outflows are related to central accretion properties or related to local physical properties of NLRs (narrow emission line regions). Here, the reported strong linear correlation with the Spearman Rank correlation coefficient 0.75 can be expected under the assumption of AGN (active galactic nuclei) feedback driven outflows, through a large sample of 535 SDSS quasars with reliable blue-shifted broad [OIII] components. Moreover, there are much different detection rates for broad blue-shifted and broad red-shifted [OIII] components in quasars, and no positive correlation can be found between shifted velocity and line width of the broad red-shifted [OIII] components, which provide further and strong evidence to reject possibility of local outflows in NLRs leading to the broad blue-shifted [OIII] components in quasars. Thus, the strong linear correlation can be treated as strong evidence for the broad blue-shifted [OIII] components as better indicators of outflows related to central engine in AGN. Furthermore, rather than central BH masses, Eddington ratios and continuum luminosities have key roles on properties of the broad blue-shifted [OIII] components in quasars.

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Zhang XueGuang. 2021-01-07. On strong correlation between shifted velocity and line width of broad blue-shifted [OIII] components in quasars. https://arxiv.org/abs/2101.02465

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