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Date and Time of the Query: 2018-12-16 T07:01:29 PST
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For refcode 2007ApJ...658..203H:
Retrieve 1119 NED objects in this reference.
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Copyright by American Astronomical Society. Reproduced by permission
2007ApJ...658..203H The VLBA Imaging and Polarimetry Survey at 5 GHz J. F. Helmboldt, G. B. Taylor, S. Tremblay, C. D. Fassnacht, R. C. Walker, S. T. Myers, L. O. Sjouwerman, T. J. Pearson, A. C. S. Readhead, L. Weintraub, N. Gehrels, R. W. Romani, S. Healey, P. F. Michelson, R. D. Blandford, and G. Cotter Abstract. We present the first results of the VLBA Imaging and Polarimetry Survey (VIPS), a 5 GHz VLBI survey of 1127 sources with flat radio spectra. Through automated data reduction and imaging routines, we have produced publicly available I, Q, and U images and have detected polarized flux density from 37% of the sources. We have also developed an algorithm to use each source's I image to automatically classify it as a pointlike source, a core jet, a compact symmetric object (CSO) candidate, or a complex source. Using data from the Sloan Digital Sky Survey (SDSS), we have found no significant trend between optical flux and 5 GHz flux density for any of the source categories. Using the velocity width of the H{beta} emission line and the monochromatic luminosity at 5100 Angstrom to estimate the central black hole mass, M_BH_, we have found a weak trend between M_BH_ and 5 GHz luminosity density for objects with SDSS spectra. The mean ratio of the polarized to total 5 GHz flux density for VIPS sources with detected polarized flux density ranges from 1% to 20% with a median value of about 5%. We have also found significant evidence that the directions of the jets in core-jet systems tend to be perpendicular to the electric vector position angles (EVPAs). The data are consistent with a scenario in which ~24% of the polarized core jets have EVPAs that are antialigned with the directions of their jet components and that have a substantial amount of Faraday rotation. In addition to these initial results, plans for future follow-up observations are discussed. Key words: Catalogs, Galaxies: Active, Galaxies: Jets, Galaxies: Nuclei, Radio Continuum: Galaxies, Surveys, Techniques: Image Processing
Retrieve 1119 NED objects in this reference.
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