The 6dF Galaxy Survey


6dF Galaxy Survey Target Density (courtesy Lachlan Campbell)

The 6dF Galaxy Survey is a whole southern sky redshift/peculiar velocity survey based on NIR selection from 2MASS and DENIS data. The unique aspects of this survey were the prime reason that 6dF was approved. Observations began in mid-2001, and up to 75% of scheduled UK Schmidt Telescope time is currently allocated to the survey.

A Science Advisory Group (6dFSAG) has been set-up by the AAT Board to provide scientific leadership and direction for the survey, to formulate a detailed implementation plan and to advise the Board of progress.

Latest survey progress chart

Survey Details

  • The 6dF redshift survey is a 2.17micron K-band (K<13) selected galaxy sample from the 2MASS Extended Source Catalogue (XSC)
  • Star/galaxy separation is checked against the higher resolution DENIS I-band imaging
  • About 120,000 redshifts will be obtained over 15,000sq.deg in ~3 years with an estimated survey completion date of mid-2005.
  • Survey will also include fainter galaxies than K=13 to be complete to H=13.5, J=14.3 & B=16.5
  • An adaptive tiling scheme is used for optimum observing efficiency
  • The survey is non-proprietorial and data are being released at one-year intervals
  • The 6dF Early Data Release is now available on-line from WFAU

    •  

     

    The K-band is closely related to the old stellar population luminosity and hence galaxy mass whilst minimising both internal and external extinction. It is also unbiased with respect to recent star formation.  The survey sample also incorporates a large number of additional targets selected following an announcement of opportunity in 2000.
     

    The 6dF peculiar velocity survey

    The primary goal of the second phase of the 6dF survey is to measure peculiar velocities over the entire southern sky. 2MASS and DENIS photometry will be combined with the observed velocity dispersions for a subset of 15,000 early type galaxies with V<15,000 km/s to obtain D_n-sigma distances. This phase is being carried out concurrently with the main survey, and will finish at the same time.

    Currently, all observations are made with two VPH gratings: 580V to provide the intermediate-dispersion data for the peculiar velocity survey and 425R to provide low-dispersion red data for the redshift survey. These two gratings are mounted on an interchangeable slide, minimising dead-time between grating changes.
     

    The roles of AAO, RSAA and WFAU

    Responsibility for carrying out the 6dF Galaxy Survey is borne primarily by AAO, but some aspects of the survey are being conducted by the Research School of Astronomy and Astrophyicics of the Australian National University (RSAA) and the Wide-field Astronomy Unit of the University of Edinburgh (WFAU).

    The AAO has prime responsibility to operate and manage 6dF; support configuration, positioning and data reduction software; and provide operational support for the facility including observations, day-to-day maintenance, repairs and upgrades. RSAA support includes redshift and velocity-dispersion determination from the reduced spectra (and maintaining the software to achieve that), updating the input catalogue and feeding revisions (and survey results) to AAO. The WFAU involvement includes the construction and maintenance of the database of survey data products, and ensuring community access to them via a www interface


    Pages maintained by: Fred Watson, AAO

    e-mail: fgw@aaocbn.aao.gov.au

    Last revision: 7 November 2003