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Two-phase models of disk-driven outflows in active galactic nuclei with combined hydromagnetic and radiative driving.

机译:结合水磁和辐射驱动的主动银河核中磁盘驱动的流出的两阶段模型。

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摘要

We present a semianalytic model of steady-state magnetically and radiatively driven disk outflows in Active Galactic Nuclei consisting of a continuous wind with embedded clouds. The continuous outflow is launched from narrow sector on the disk surface as a centrifugally driven wind. Clouds are either uplifted from the disk by the ram pressure of the continuous outflow or are transient, created and destroyed throughout the wind. The inner regions of the outflow shield the outer portions from the strong ionizing central continuum, enabling gas in the outer regions to be radiatively accelerated. This thesis first describes the model in detail, outlines the tests used to verify its accuracy, and then compares it to other outflow models already in use. We present representative solutions of the model to explore the dependence of outflow properties on the relevant physical parameters, and also explore the impact of “ephemeral” (transient) condensations present throughout the wind vs. the disk-launched clouds introduced with the original model.; We find agreement with previous models where such comparisons are possible, although we also find that our more detailed radiative acceleration calculations do differ from some previous 2D hydrodynamical simulations. As in previous work, we find that radiative acceleration can have a significant impact on wind kinematics near the surface of the disk. We determine that continuum driving dominates line driving in the wind, whereas line driving accounts for most of the cloud acceleration. Also, when the winds contain dust, radiative acceleration can modify their terminal velocities by 80% over pure centrifugally-driven outflows. Finally, we find that only “ephemeral” clouds can substantially change the structure of the wind for cloud wind: condensations launched from the accretion disk rapidly accelerate out, of the thin wind and do not significantly affect the geometry or kinematics of the wind.
机译:我们提出了一个半解析模型,用于在主动银河核中由稳态风磁和辐射驱动的磁盘流出,其中包括连续的风和嵌入的云。连续流出是作为离心驱动的风从磁盘表面上的狭窄扇区发出的。连续流出的夯头压力使云层从圆盘上抬升,或者在整个风中都是短暂的,产生和破坏的。流出物的内部区域使外部区域免受强电离的中央连续区的影响,从而使外部区域中的气体辐射加速。本文首先详细描述了该模型,概述了用于验证其准确性的测试,然后将其与已经使用的其他流出模型进行了比较。我们提出了该模型的代表性解决方案,以探讨流出特性对相关物理参数的依赖性,并探讨在整个风中相对于原始模型引入的盘状云对“短暂”(瞬态)凝结的影响。 ;尽管我们也发现我们更详细的辐射加速度计算确实与某些先前的2D流体动力学模拟有所不同,但我们发现与可以进行此类比较的先前模型相一致。与以前的工作一样,我们发现辐射加速度可能会对磁盘表面附近的风运动产生重大影响。我们确定连续驾驶在风中行车驾驶中占主导地位,而行车驾驶则是大部分云加速的原因。同样,当风中包含灰尘时,辐射加速度可以使它们的最终速度比纯离心驱动的流出量高80%。最后,我们发现对于 M˙ cloud ≲ 而言,只有“短暂”的云才能实质改变风的结构。 math> M˙ wind :从吸积盘发出的凝结迅速从薄弱的风中加速出来,并且不会显着影响风的几何学或运动学。

著录项

  • 作者

    Everett, John Eric.;

  • 作者单位

    The University of Chicago.;

  • 授予单位 The University of Chicago.;
  • 学科 Physics Astronomy and Astrophysics.
  • 学位 Ph.D.
  • 年度 2003
  • 页码 90 p.
  • 总页数 90
  • 原文格式 PDF
  • 正文语种 eng
  • 中图分类 天文学;
  • 关键词

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