VLBI Polarimetry of 177 Sources from the Caltech-Jodrell Bank Flat-spectrum Survey
نویسندگان
چکیده
We present VLBA observations and a statistical analysis of 5 GHz VLBI polarimetry data from 177 sources in the Caltech-Jodrell Bank flat-spectrum (CJF) survey. The CJF survey, a complete, flux-density-limited sample of 293 extragalactic radio sources, gives us the unique opportunity to compare a broad range of source properties for quasars, galaxies and BL Lacertae objects. We focus primarily on jet properties, specifically the correlation between the jet axis angle and the polarization angle in the core and jet. A strong correlation is found for the electric vector polarization angle in the cores of quasars to be perpendicular to the jet axis. Contrary to previous claims, no correlation is found between the jet polarization angle and the jet axis in either quasars or BL Lac objects. With this large, homogeneous sample we are also able to investigate cosmological issues and AGN evolution. Subject headings: galaxies: active – galaxies: jets – galaxies: nuclei – radio continuum: galaxies; polarimetry
منابع مشابه
The Caltech–Jodrell Bank VLBI Surveys
The Caltech–Jodrell Bank VLBI surveys of bright extragalactic radio sources north of declination 35 were carried out between 1990 and 1995 using the Mark-II system, achieving images with a resolution of about 1 mas at 5 GHz. The CJ1 survey (together with the older ‘PR’ survey) includes 200 objects with 5 GHz flux density greater than 0.7 Jy; the CJ2 survey includes 193 flat-spectrum sources wit...
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