| 17th of March 2015 |
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| The ASKAP HI All Sky Survey |
| by Bärbel Koribalski (CASS) |
| WALLABY is the "ASKAP HI All-Sky Survey", a precursor for
future, much deeper SKA Phase 1 & Phase 2 neutral hydrogen (HI) surveys. With
an integration time of ~1 year (or 8 hours per pointing) WALLABY will cover
two-thirds of the sky to redshifts of z = 0.25. Using our best source-finding
algorithms - now available as part of SoFiA (Serra et al. 2015) - we estimate that in the
survey volume around 600 000 galaxies are individually detectable in the 21-cm
line of neutral atomic hydrogen (e.g., Duffy et al. 2012). We will measure the HI properties
of each galaxy and derive its distance, HI mass, total mass and dark matter
content. The vast majority of these galaxies will also be detected in the
20-cm radio continuum, obtained as part of the same survey, allowing us to
derive their unobscured star-formation rates. The 30 arcsec angular resolution
of WALLABY will allow us to identify likely optical and/or infrared galaxy
counterparts. The WALLABY team consists of ~80 researchers from around the
world, led by Bärbel Koribalski (CSIRO Astronomy and Space Science) and
Lister Staveley-Smith (UWA/ICRAR). For a brief overview of WALLABY see
Koribalski
(2012). SKA Pathfinder HI surveys, including WALLABY, are being discussed today at the 8th PHISCC Workshop. |