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标题：Magnetically aligned straight depolarization canals and the rolling Hough transform
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作者：Vibor Jelić ; David Prelogović ; Marijke Haverkorn 等
期刊名称：Astronomy & Astrophysics
印刷版ISSN：0004-6361
电子版ISSN：1432-0746
出版年度：2018
卷号：615
DOI：10.1051/0004-6361/201833291
语种：English
出版社：EDP Sciences
摘要：Aims. We aim to characterize the properties of the straight depolarization canals detected in the Low Frequency Array (LOFAR) polarimetric observations of a field centered on the extragalactic source 3C 196. We also compare the canal orientations with magnetically aligned HIfilaments and the magnetic field probed by polarized dust emission.Methods. We used the rolling Hough transform (RHT) to identify and characterize the orientation of the straight depolarization canals in radio polarimetric data and the filaments in HIdata.Results. The majority of the straight depolarization canals and the Hi filaments are inclined by ~10° with respect to the Galactic plane and are aligned with the plane-of-sky magnetic field orientation probed by thePlanckdust polarization data. The other distinct orientation, of −65° with respect to the Galactic plane, is associated with the orientation of a bar-like structure observed in the 3C 196 field at 350 MHz.Conclusions. An alignment between three distinct tracers of the (local) interstellar medium (ISM) suggests that an ordered magnetic field plays a crucial role in confining different ISM phases. The majority of the straight depolarization canals are a result of a projection of the complicated 3D distribution of the ISM. The RHT analysis is a robust method for identifying and characterizing the straight depolarization canals observed in radio-polarimetric data.
关键词：enISM: generalISM: magnetic fieldsISM: structureradio continuum: ISMtechniques: interferometrictechniques: polarimetric