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arXiv 1601.03090astro-ph.GAastro-ph.HE
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活动星系核与宿主星系核取向的反射光谱研究

The view of AGN-host alignment via reflection spectroscopy

Matthew J. Middleton, Michael L. Parker, Christopher S. Reynolds, Andrew C. Fabian, Anne M. Lohfink

摘要:

活动星系核(AGN)的燃料-通过星系盘传播的物质或通过较小的合并-预计会在次pc盘相对于宿主星系的恒星盘的排列上留下印记。确定内盘的倾斜度通常依赖于喷流的发射角,这里我们使用的是活动星系核样本的反射拟合得出的倾斜度。我们确定未建模的Fe XXV/XXVI功能的扭曲效果,并通过广泛的模拟,确定使用relxill相比,reflionx的光盘倾斜度的差异。我们比较了内盘倾角的宿主星系恒星盘来自哈勃公式,并通过蒙特卡罗模拟,发现一个强烈的缺乏相关性(在>> 5西格玛),这意味着要么通过合并广泛的饲料,如果我们假设样本是均匀的,或辐射盘扭曲扭曲我们的看法的排放。然而,我们发现,通过删除一个小的(~1/5)AGN的子集,剩余的样本是一致的随机抽样的基础1:1的相关性(在3西格玛水平)。一个异质的样本可能意味着我们的观点不是由辐射盘翘曲主导的,而是由不同的馈送机制主导的,其中大多数与共面吸积一致(尽管这可能是选择偏差的结果),而一个较小但并非微不足道的部分可能是由宿主星系最近历史上的微小合并所推动的。

英文摘要:

The fuelling of active galactic nuclei (AGN) - via material propagated through the galactic disc or via minor mergers - is expected to leave an imprint on the alignment of the sub-pc disc relative to the host galaxy's stellar disc. Determining the inclination of the inner disc usually relies on the launching angle of the jet; here instead we use the inclination derived from reflection fits to a sample of AGN. We determine the distorting effect of unmodeled Fe XXV/XXVI features and, via extensive simulations, determine the difference in disc inclination resulting from the use of relxill compared to reflionx. We compare inner disc inclinations to those for the host galaxy stellar disc derived from the Hubble formula and, via Monte-Carlo simulations, find a strong lack of a correlation (at >> 5-sigma) implying either widespread feeding via mergers if we assume the sample to be homogeneous, or that radiative disc warps are distorting our view of the emission. However, we find that by removing a small (~1/5) subset of AGN, the remaining sample is consistent with random sampling of an underlying 1:1 correlation (at the 3-sigma level). A heterogenous sample would likely imply that our view is not dominated by radiative disc warps but instead by different feeding mechanisms with the majority consistent with coplanar accretion (although this may be the result of selection bias), whilst a smaller but not insignificant fraction may have been fuelled by minor mergers in the recent history of the host galaxy.

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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