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arXiv 0806.2910astro-ph
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斯皮策揭示的中红外窄线鲍德温效应

The Mid-Infrared Narrow Line Baldwin Effect Revealed by Spitzer

M. Keremedjiev, L. Hao, V. Charmandaris

摘要:

本文介绍了我们用斯皮策空间望远镜的红外光谱仪在68个活动星系核(AGN)样品的5-20个$<$ m中红外谱线中发现的窄线Baldwin效应,这是谱线的等效宽度(EW)与相关连续谱线的通量之间的反相关。我们的分析揭示了[SIV] 10.51 $μ$ m、[NeII] 12.81 $μ$ m和[NeIII] 15.56 $μ$ m谱线的EW与它们的中红外连续发光度之间的明显反相关性,而[NeV] 14.32 $μ$ m谱线的Baldwin效应则不那么明显。我们认为,这种反相关是由中央活动星系核,而不是在宿主星系的环核恒星形成。我们还发现,在中红外线的窄线鲍德温效应的斜率并没有出现陡峭的电离势的增加。检查EW对爱丁顿比($L/L_{Edd}$)的依赖性,我们发现对于中红外线没有强的关系。我们的研究表明,窄线的中红外鲍德温效应是很大的不同,宽线的光学/紫外鲍德温效应,这两种效应可能是无关的。发现的反关联打开了新的可能性,在理解电离区的物理和连续再处理的尘埃。

英文摘要:

We present our discovery of a narrow-line Baldwin effect, an anti-correlation between the equivalent width (EW) of a line and the flux of the associated continuum, in 5-20$μ$m mid-infared lines from a sample of 68 Active Galactic Nuclei (AGN), located at z$<$0.5, observed with the Infrared Spectrograph on the {\it Spitzer Space Telescope}. Our analysis reveals a clear anti-correlation between the EW of the [SIV] 10.51$μ$m, [NeII] 12.81$μ$m, and [NeIII] 15.56$μ$m lines and their mid-IR continuum luminosities, while the Baldwin effect for [NeV] 14.32$μ$m is not as obvious. We suggest that this anti-correlation is driven by the central AGN and not circumnuclear star formation in the host galaxy. We also find that the slope of the narrow-line Baldwin effect in the mid-infrared does not appear to steepen with increasing ionization potential. Examining the dependence of the EW to the Eddington Ratio ($L/L_{Edd}$) we find no strong relationship for mid-IR lines. Our study indicates that the narrow-line mid-infrared Baldwin Effect is quite different from the broad-line optical/UV Baldwin effect and it is possible that the two effects are unrelated. The discovered anti-correlations open new possibilities in the understanding the physics of the ionizing region and the continuum reprocessing by dust.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

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