The VLBA Imaging and Polarimetry Survey at 5 GHz

Journal article

We present the first results of the VLBA Imaging and Polarimetry Survey (VIPS), a 5 GHz VLBI survey of 1,127 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 point-like source, a core-jet, a compact symmetric object (CSO) candidate, or a complex source. 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 is consistent with a scenario in which ~24% of the polarized core-jets have EVPAs that are anti-aligned with the directions of their jet components and which have a substantial amount of Faraday rotation. In addition to these initial results, plans for future follow-up observations are discussed.

Authors: Helmboldt, J; Taylor, G; Tremblay, S; Fassnacht, C; Walker, R

• Publication status: Published
• Journal: Astrophys.J.
• Volume: 658
• Issue: 1
• Pages: 203-216
• Publication date: 2006-11-14
• DOI: 10.1086/511005
• EISSN: 1538-4357
• ISSN: 0004-637X
• Language: English
• Keywords: astro-ph