Galactic All Sky Survey

The entire GASS dataset shown in a ZEA projection centered on the south celestial pole with 0 hr right ascension at the top and with RA increasing counter-clockwise. The colors correspond to integrations over velocity chunks of ~40 km/s as indicated by the bar on the right of the image. The intensity of each color corresponds to the brightness temperature integrated over the 40 km/s velocity chunk, and is scaled logarithmically as shown by the horizontal extent of the color bar. Credit: S. Janowiecki

The Parkes Galactic All Sky Survey (GASS) is a survey of the atomic hydrogen (HI) emission in the Milky Way for the entire sky south of δ = +1° using the thirteen beam 20 cm multibeam receiver on the Parkes Radio Telescope. GASS covers all Milky Way velocities between LSR -400 km/s and 500 km/s. GASS is the most sensitive fully-sampled survey of Galactic HI ever made in the Southern sky. Survey goals include a better understanding of the interaction of the Milky Way disk and halo and the nature of high and intermediate velocity clouds (HVCs and IVCs).

The first data release of GASS provides spectra and velocity integrated maps with a 16 arcmin angular resolution, 0.82 km/s spectral resolution and an rms sensitivity of 57 mK (McClure-Griffiths et al. 2009). These products are available here under the link "Data". We ask that any use of GASS data or images cite the McClure-Griffiths et al. (2009) reference.

The second data release is planned for mid 2009 and will provide full stray radiation FITS cubes of the survey.

Questions about GASS and its data products can be addressed to: Naomi McClure-Griffiths (Naomi.McClure-Griffiths < at > csiro.au)