BROADBAND RADIO POLARIMETRY AND FARADAY ROTATION OF 563 EXTRAGALACTIC RADIO SOURCES
BROADBAND RADIO POLARIMETRY AND FARADAY ROTATION OF 563 EXTRAGALACTIC RADIO SOURCES
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563 个河外无线电源的宽带无线电偏振测量和法拉第旋转
DOI：
10.1088/0004-637x/815/1/49
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发表时间：
2015
期刊：
影响因子：
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通讯作者：
T. Franzen
中科院分区：
文献类型：
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作者：
C. Anderson;B. Gaensler;I. Feain;T. Franzen
我们提出了一个宽带分光偏振调查563离散，大多未解决的无线电源之间的1.3和2.0 GHz的数据与澳大利亚望远镜紧凑阵列。我们已经使用旋转测量合成来识别法拉第复极化源，这些对象的频率相关的极化行为表明存在的材料具有复杂的磁离子结构沿着视线（LOS）。对于被归类为法拉第复合源，我们分析了它们的无线电和多波长特性，以确定它们是否不同于法拉第简单极化源（LOS磁离子结构相对简单的源）在这些属性。我们使用这些信息来约束导致观察到的复杂性的磁离子结构的物理性质。我们检测到法拉第复杂性在12%的极化源在101“分辨率，但我们证明，潜在的信噪比限制意味着真正的百分比可能是显着更高的极化无线电源人口。我们发现，法拉第复杂的对象的属性是多种多样的，但复杂性是最经常与去极化的扩展无线电源拥有一个相对陡峭的总强度谱。我们发现银河系星际介质（ISM）中的法拉第复杂性和LOS结构之间的关联，并声称我们观察到的法拉第复杂性的一个重要部分可能会产生在ISM与电离锋附近的中性氢结构的接口。星系团环境和内部产生的法拉第复杂性在某些情况下提供了可能的替代解释。
We present a broadband spectropolarimetric survey of 563 discrete, mostly unresolved radio sources between 1.3 and 2.0 GHz using data taken with the Australia Telescope Compact Array. We have used rotation-measure synthesis to identify Faraday-complex polarized sources, those objects whose frequency-dependent polarization behavior indicates the presence of material possessing complicated magnetoionic structure along the line of sight (LOS). For sources classified as Faraday-complex, we have analyzed a number of their radio and multiwavelength properties to determine whether they differ from Faraday-simple polarized sources (sources for which LOS magnetoionic structures are comparatively simple) in these properties. We use this information to constrain the physical nature of the magnetoionic structures responsible for generating the observed complexity. We detect Faraday complexity in 12% of polarized sources at ∼1′ resolution, but we demonstrate that underlying signal-to-noise limitations mean the true percentage is likely to be significantly higher in the polarized radio source population. We find that the properties of Faraday-complex objects are diverse, but that complexity is most often associated with depolarization of extended radio sources possessing a relatively steep total intensity spectrum. We find an association between Faraday complexity and LOS structure in the Galactic interstellar medium (ISM) and claim that a significant proportion of the Faraday complexity we observe may be generated at interfaces of the ISM associated with ionization fronts near neutral hydrogen structures. Galaxy cluster environments and internally generated Faraday complexity provide possible alternative explanations in some cases.