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arXiv 1410.6552astro-ph.GA
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发光型II AGN - I的IFU观测。无处不在的风的证据

IFU observations of luminous type II AGN - I. Evidence for ubiquitous winds

Rebecca McElroy, Scott M. Croom, Michael Pracy, Rob Sharp, I-Ting Ho, Anne M. Medling

摘要:

本文报道了17个发光(log(L[O III]/L_Sun)> 8.7)局域(z < 0.11)II型活动星系核的观测结果。我们的目标是调查的流行和性质的活动星系核驱动的外流在这些星系结合运动学和电离诊断信息。我们使用非参数方法(例如W80,包含80%线通量的宽度)来评估目标中心区域的线宽。每个星系中W80的最大值在400 - 1600 km/s之间,平均值为790 +- 90 km/s。如此高的速度强烈暗示这些活动星系核正在驱动电离外流。采用多重高斯拟合方法对银河系的速度结构进行了分解。14/17的目标在其中心区域的电离气体中需要3个独立的运动学分量。这些拟合的最宽分量具有FWHM = 530 - 2520 km/s,平均值为920 +- 50 km/s。通过同时拟合Hβ/[O III]和Hα/[N II]复合物,我们构建了每个组分的电离诊断图。13/17的星系显示出[N II]/Hα比值与气体速度色散之间的显著(> 95%)相关性。这样的相关性是自然的结果,从冲击激发电离的贡献,我们认为,这表明,从这些活动星系核的外流直接影响周围的ISM星系内。

英文摘要:

We present observations of 17 luminous (log(L[O III]/L_Sun) > 8.7) local (z < 0.11) type II AGN. Our aim is to investigate the prevalence and nature of AGN driven outflows in these galaxies by combining kinematic and ionization diagnostic information. We use non-parametric methods (e.g. W80, the width containing 80% of the line flux) to assess the line widths in the central regions of our targets. The maximum values of W80 in each galaxy are in the range 400 - 1600 km/s, with a mean of 790 +- 90 km/s. Such high velocities are strongly suggestive that these AGN are driving ionized outflows. Multi-Gaussian fitting is used to decompose the velocity structure in our galaxies. 14/17 of our targets require 3 separate kinematic components in the ionized gas in their central regions. The broadest components of these fits have FWHM = 530 - 2520 km/s, with a mean value of 920 +- 50 km/s. By simultaneously fitting both the Hβ/[O III] and Hα/[N II] complexes we construct ionization diagnostic diagrams for each component. 13/17 of our galaxies show a significant (> 95 %) correlation between the [N II]/Hα ratio and the velocity dispersion of the gas. Such a correlation is the natural consequence of a contribution to the ionization from shock excitation and we argue that this demonstrates that the outflows from these AGN are directly impacting the surrounding ISM within the galaxies.

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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