The Southern Galactic Plane Survey: Polarized Radio Continuum Observations and Analysis

The Southern Galactic Plane Survey (SGPS) is a radio survey in the 21 cm H I line and in 1.4 GHz full-polarization continuum, observed with the Australia Telescope Compact Array and the Parkes 64m single dish telescope. The survey spans a Galactic longitude of 253 < l < 358 and a latitude of |b| < 1 at a resolution of 100 arcsec and a sensitivity below 1 mJy/beam. This paper presents interferometer only polarized continuum survey data and describes the data taking, analysis processes and data products. The primary data products are the four Stokes parameters I, Q, U, and V in 25 overlapping fields of 5.5 by 2, from which polarized intensity, polarization angle and rotation measure are calculated. We describe the effects of missing short spacings, and discuss the importance of the polarized continuum data in the SGPS for studies of fluctuations and turbulence in the ionized interstellar medium and for studying the strength and structure of the Galactic magnetic field. Subject headings: ISM: magnetic fields — H ii regions — ISM: structure — techniques: polarimetric — radio continuum: ISM — turbulence