THE GENESIS OF MORPHOLOGIES IN EXTENDED RADIO SOURCES: X-SHAPES, OFF-AXIS DISTORTIONS, AND GIANT RADIO SOURCES
THE GENESIS OF MORPHOLOGIES IN EXTENDED RADIO SOURCES: X-SHAPES, OFF-AXIS DISTORTIONS, AND GIANT RADIO SOURCES
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DOI：
10.1088/0004-637x/695/1/156
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发表时间：
2008-11
期刊：
影响因子：
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通讯作者：
L. Saripalli;R. Subrahmanyan
中科院分区：
文献类型：
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作者：
L. Saripalli;R. Subrahmanyan
我们研究双射电源的形态和无线电光学位置角偏移-相对于主星系的主轴无线电轴的相对取向之间的关系。该研究是针对射电源的代表性样本，即附近（红移z < 0.5）的3CRR源，并分别针对巨射电源和X形射电源的样本进行的。我们发现，无线电形态特征依赖于无线电-光学位置角偏移和源是长轴源还是短轴源。证据表明，各向异性的气体环境，有关的宿主星系的椭圆率，导致源的线性尺寸的演变，在无线电波瓣，离轴波瓣扭曲和翅膀的形成回流的强度，和X形射电源依赖于无线电光学位置角偏移。我们确定了一类X形的射电源，这是要么边缘变暗或缺乏热点，似乎有内部双打表明重新启动的活动。我们建议一个共同的形成机制，需要回流，这些显然FR-I X形射电源以及边缘增亮的X形源。
We examine relationships between the morphology in double radio sources and the radio–optical position angle offset—the relative orientation of the radio axis with respect to the major axis of the host galaxy. The study was done for a representative sample of radio sources, the nearby (redshift z < 0.5) 3CRR sources, and separately for samples of giant radio sources and X-shaped radio sources. We find that radio morphological features have a dependence on the radio-optical position angle offset and on whether the source is a major- or minor-axis source. The evidence indicates an anisotropic gas environment, related to the ellipticity of the host galaxy, that causes the source linear size evolution, strength of backflow in the radio lobes, off-axis lobe distortions and the formation of wings, and X-shaped radio sources to depend on the radio–optical position angle offset. We identify a class of X-shaped radio sources, which are either edge-darkened or lacking hotspots, and appear to have inner doubles suggesting a restarting of activity. We suggest a common formation mechanism, requiring backflows, for these apparently FR-I X-shaped radio sources as well as the edge-brightened X-shaped sources.