Welcome to the new version of CaltechAUTHORS. Login is currently restricted to library staff. If you notice any issues, please email coda@library.caltech.edu
Published September 1, 2007 | Published
Journal Article Open

Radio Polarimetry of the ELAIS N1 Field: Polarized Compact Sources

Abstract

We present deep polarimetric observations at 1420 MHz of the European Large Area ISO Survey North 1 region (ELAIS N1) as part of the Dominion Radio Astrophysical Observatory Planck Deep Fields project. By combining closely spaced aperture synthesis fields, we image a region of 7.43 deg^2 to a maximum sensitivity in Stokes Q and U of 78 μJy beam^(-1), and detect 786 compact sources in Stokes I. Of these, 83 exhibit polarized emission. We find that the differential source counts (log N-log p) for polarized sources are nearly constant down to p > 500 μJy, and that these faint polarized radio sources are more highly polarized than the strong source population. The median fractional polarization is 4.8% ± 0.7% for polarized sources with Stokes I flux density between 10 and 30 mJy, approximately 3 times larger than sources with I > 100 mJy. The majority of the polarized sources have been identified with galaxies in the Spitzer Wide Area Infrared Extragalactic Survey (SWIRE) image of ELAIS N1. Most of the galaxies occupy regions in the IRAC 5.8 μm/3.6 μm versus 8.0 μm/4.5 μm color-color diagram associated with dusty AGNs, or with ellipticals with an aging stellar population. A few host galaxies have colors that suggests significant PAH emission in the near-infrared. A small fraction, 12%, of the polarized sources are not detected in the SWIRE data. None of the polarized sources in our sample appears to be associated with an actively star-forming galaxy.

Additional Information

© 2007 American Astronomical Society. Print publication: Issue 1 (2007 September 1); received 2007 February 27; accepted for publication 2007 May 11. Observations and research on the DRAO Planck Deep Fields are supported by the Natural Sciences and Engineering Research Council of Canada and the National Research Council Canada. Ev Sheehan of DRAO was instrumental in improving the sensitivity of the DRAO Synthesis Telescope, with the outcome recorded in this paper. We are indebted to him for his skill and dedication to this difficult task. The Dominion Radio Astrophysical Observatory is operated as a National Facility by the National Research Council of Canada.

Attached Files

Published - TAYapj07.pdf

Files

TAYapj07.pdf
Files (525.7 kB)
Name Size Download all
md5:43ae08b6076c26a8da850e4f85aba847
525.7 kB Preview Download

Additional details

Created:
August 22, 2023
Modified:
October 19, 2023