Survey Design

As one of the ten ASKAP-supported survey science projects, DINGO directly addresses a key science goal of ASKAP; studying the evolution of HI from the current epoch to a time when the Universe was two-thirds is present age.

We propose 21cm spectral line observations of the GAMA survey regions in a two-tiered strategy extending from redshift zero to ~0.4, providing a legacy dataset spanning cosmologically representative volumes. In excess of 104 HI sources are expected for 7,500 hrs of combined observing time.

Measurements will be made of the evolution of key cosmological distributions and quantities including HI, the HI mass function, the 2pt correlation function and the halo occupation distribution function. Data from GAMA and associated major multi-wavelength surveys (HERSCHEL-ATLASVISTA-VIKINGVST-KIDSCHFT-LS) will be used to provide quantitative morphological measurements, optical line indices, star-formation rates, stellar and dust mass estimates, environmental markers, along with 250k confirmed target redshifts.

We will combine these with ASKAP data to enable a thorough study of the co-evolution of the stellar, baryonic, and dark matter content of galaxies, constituting the first comprehensive study of these components over the past 4 Gyr with well matched sensitivities, resolution and depths. In addition, the independent multi-wavelength datasets will be used for cross-correlation and HI spectral stacking techniques to extend the redshift limit at which the fundamental HI parameter and distribution measurements can be made.

 

Proposed Survey Design

The full DINGO survey is arranged in two tiers, and will make use of the unique wide field of view of ASKAP to study the HI content of galaxies over the past 4 billion years:

  • DINGO-Deep: 5x500h fields, 0<z<0.26, to be located in GAMA/WAVES regions
  • DINGO-Ultradeep: 2x2500h fields, 0.1<z<0.43, to be located in southern GAMA G23 region (also part of WAVES-Deep).
DINGO-Deep: 5x500h fields, 0<z<0.26, to be located in GAMA/WAVES regions
DINGO-Ultradeep: 2x2500h fields, 0.1<z<0.43, to be located in southern GAMA G23 region (also part of WAVES-Deep).

 

A comparison with WALLABY (all-sky HI emission) and FLASH (HI absorption). DINGO-Deep field locations indicative.
Number counts and HI mass as a function of z/lookback time.