S-PASS data set


The S-band Polrisation All Sky Survey (S-PASS) is a project to map the polarised emission at 2.3 GHz of the entire southern sky at Dec < -1 deg, with the Parkes radio telescope, located in NSW, Australia, and operated by CSIRO-CASS.

In this site we publicly release the DR1 maps.

DR1 maps are for the three Stokes parameters I, Q, U, with the entire frequency range binned in one channel.

A second DR2 will be about the spectropolarimetric data cube and will be released at a later stage.


Refer to the following paper for full details and description of maps, specs, and how the observations were designed and conducted:

Carretti E, Haverkorn M, Staveley-Smith L, Bernardi G, Gaensler B M, Kesteven M, Poppi S, Brown S, Crocker R, Purcell C R, Schnitzeler D, Sun X, 2019, MNRAS, accepted for publication, arXiv:1903.09420

Main specs are reported here below:

  • Galactic coordinates
  • Aitoff projection or HEALPix maps
  • pixel nside for HEALPix maps: 1024
  • pixel size in AITOFF projection: 3.44 arcmin (see FITS file header for exact value)
  • effective central frequency = 2303 MHz
  • BW = 168 MHz (actual frequency ranges: 2176-2216 + 2272-2400 MHz)
  • FWHM = 8.9 arcmin
  • unit: Kelvin (full-beam Brightness Temperature)
  • K-to-Jy conversion factor = 1.19 Jy/K
  • Q & U maps are zero-offset calibrated by design of the scanning strategy and map-making used for S-PASS
  • Stokes I has been zero-offset calibrated with absolute flux observations available in literature.
  • Stokes Q & U sensitivity: sensitivity map is provided (in K, use same conversion factor to get that in Jy/b)
  • Stokes I sensitivity: confusion limit limited to 9 mK = 11 mJy/beam
  • Stokes I zero-offset calibration error: 70 mK = 83 mJy/beam