Interactions of a Light Hypersonic Jet with a Nonuniform Interstellar Medium
Interactions of a Light Hypersonic Jet with a Nonuniform Interstellar Medium
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轻高超音速射流与非均匀星际介质的相互作用
DOI：
10.1086/520640
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发表时间：
2007
期刊：
影响因子：
--
通讯作者：
G. Bicknell
中科院分区：
文献类型：
--
作者：
R. Sutherland;G. Bicknell
我们提出了三维模拟的相互作用的轻高超声速喷流与非均匀的热和磁支持的磁盘在椭圆星系。这些模拟适用于银河系外射电源的GPS/CSS阶段。在这些模拟中的星际介质包括一个传统的热（T ~ 107 K）组件连同一个温暖的（T ~ 104 K）的磁支撑盘，其局部密度是由对数正态密度分布描述，其空间结构是从分形幂律实现。我们的模型作为一个轻，超音速非相对论性流的参数选择与相对论性射流与动能以上的FR 1/FR 2突破一致的射流。我们确定了非均匀星际介质中这种喷流演化的四个阶段：（1）初始的“洪水和通道”阶段，其特征是高压气体在ISM中找到不断变化的弱点，流过随着时间的推移形成和改革的通道;（2）球形的、能量驱动的气泡相，其中气泡大于盘尺度，但是射流在靠近核的地方保持完全被破坏;（3）随后的快速射流爆发阶段，其中射流脱离最后的阻挡稠密云，再次变得准直，并穿透球形气泡;和（4）经典阶段，其中射流以动量主导的方式传播，类似于单组分热晕中的射流，导致了经典的射流-茧-弓形激波结构。在模拟中的质量传输进行了研究，我们提出了一个模型的形态和组件自行车在良好的研究紧凑的对称对象4C 31.04。
We present three-dimensional simulations of the interaction of a light hypersonic jet with an inhomogeneous thermal and turbulently supported disk in an elliptical galaxy. These simulations are applicable to the GPS/CSS phase of extragalactic radio sources. The interstellar medium in these simulations consists of a conventional hot (T ~ 107 K) component together with a warm (T ~ 104 K) turbulently supported disk whose local density is described by a lognormal density distribution and whose spatial structure is realized from a fractal power law. We model the jet as a light, supersonic nonrelativistic flow with parameters selected to be consistent with a relativistic jet with kinetic power just above the FR1/FR2 break. We identify four generic phases in the evolution of such a jet with the inhomogeneous interstellar medium: (1) an initial "flood and channel" phase, where progress is characterized by high-pressure gas finding changing weak points in the ISM, flowing through channels that form and reform over time; (2) a spherical, energy-driven bubble phase, where the bubble is larger than the disk scale, but the jet remains fully disrupted close to the nucleus; (3) a subsequent, rapid, jet break-out phase where the jet breaks free of the last obstructing dense clouds, becomes collimated once more, and pierces the spherical bubble; and (4) a classical phase, where the jet propagates in a momentum-dominated fashion similar to jets in single-component hot halos, leading to the classical jet-cocoon-bow shock structure. Mass transport in the simulations is investigated, and we propose a model for the morphology and component proper motions in the well-studied compact symmetric object 4C 31.04.