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arXiv 1305.2181astro-ph.CO
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远UV中的类星体流出和AGN反馈:QSO的HST/COS观测HE0238-1904

Quasar Outflows and AGN Feedback in the Far UV: HST/COS Observations of QSO HE0238-1904

Nahum Arav, Benoit Borguet, Carter Chamberlain, Doug Edmonds, Charles Danforth

摘要:

在静止坐标系500-1000埃的类星体外流的光谱观测具有巨大的诊断能力。我们目前的分析这样的数据,从三个重要的离子的吸收槽测量:第一,O IV和O IV*,使我们能够获得高电离流出的AGN的距离;第二,Ne VIII和Mg X是敏感的非常高的电离相的流出。他们推断的柱密度,结合那些槽从O VI,N IV,和H I,产生两个重要的结果:1)流出显示两个电离阶段,其中高电离相携带的大部分材料。这与X射线热吸收体研究中看到的情况相似。此外,推断低电离相具有10^(-5)-10 ^(-6)的体积填充因子。2)从O IV到O IV* 柱密度比和电离参数的知识,我们确定3000 pc的距离。从外流到中央源头。由于这是典型的高电离外流,我们可以确定外流的质量通量和动力学光度的稳健值:分别为每年40个太阳质量和10^45尔格/秒,其中后者大致等于热光度的1%。在一个典型的高电离风中测得如此大的动力学光度和质量流率表明类星体外流是活动星系核反馈机制的主要贡献者。

英文摘要:

Spectroscopic observations of quasar outflows at rest-frame 500-1000 Angstrom have immense diagnostic power. We present analyses of such data, where absorption troughs from three important ions are measured: first, O IV and O IV* that allow us to obtain the distance of high ionization outflows from the AGN; second, Ne VIII and Mg X that are sensitive to the very high ionization phase of the outflow. Their inferred column densities, combined with those of troughs from O VI, N IV, and H I, yield two important results: 1) The outflow shows two ionization phases, where the high ionization phase carries the bulk of the material. This is similar to the situation seen in x-ray warm absorber studies. Furthermore, the low ionization phase is inferred to have a volume filling factor of 10^(-5)-10^(-6). 2) From the O IV to O IV* column density ratio, and the knowledge of the ionization parameter, we determine a distance of 3000 pc. from the outflow to the central source. Since this is a typical high ionization outflow, we can determine robust values for the mass flux and kinetic luminosity of the outflow: 40 solar masses per year and 10^45 ergs/s, respectively, where the latter is roughly equal to 1% of the bolometric luminosity. Such a large kinetic luminosity and mass flow rate measured in a typical high ionization wind suggests that quasar outflows are a major contributor to AGN feedback mechanisms.

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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