6dF is a
multi-object spectroscopy system operated by the AAO on the 1.2-m UK Schmidt
It uses an off-telescope robotic fibre positioner to configure up to 150 fibres on interchangeable field-plate units, which replace the original photographic plateholders of the telescope. The system was built in-house by AAO and commissioned during the first half of 2001.
Until August 2005, the instrument was used for 6dF Galaxy Survey observations and common-user non-survey observations. Since then, however, 6dF has been exclusively used for the RAVE stellar velocity survey.
6dF's principal task during the period 2001-2005 was to carry out an all-southern-sky galaxy redshift and peculiar-velocity survey. Up to 75% of scheduled (dark/grey) telescope time was devoted to this non-proprietorial survey, which was a joint initiative of the Anglo-Australian Observatory, the Research School of Astronomy and Astrophysics of the Australian National University (RSAA), and the Wide-field Astronomy Unit of the University of Edinburgh. The survey PI was Matthew Colless (AAO). The input catalogue consisted of some 175,000 individual objects - principally K-band (K<13) selected galaxies from the 2MASS Extended Source Catalogue, although a variety of other sources are included. The Additional Targets programme allowed several auxiliary projects to be incorporated into the main survey. The final data-products consist of redshifts for some 120,000 galaxies and peculiar velocities for a volume-limited subset of about 10,000 galaxies.
Since 2005, 6dF has been used exclusively to obtain data for the externally-funded RAVE programme. RAVE (RAdial Velocity Experiment) is a project to conduct an all-sky survey of the radial velocities, metallicities and abundance ratios of up to a million stars in our Galaxy, with a limiting magnitude of I=11. The pilot RAVE project was launched in 2003, using seven bright nights per month, but since August 2005, RAVE has been scheduled on 25 nights per month. More than 300,000 high-quality spectra (with R~7500) have been obtained to date in this project, and a velocity accuracy in the range 1 to 2 km/s is routinely achieved. RAVE is an international project involving participants from 10 nations, and is expected to be completed no later than 2011. RAVE's PI is Matthias Steinmetz of Astrophysikalisches Institut Potsdam.
For objects with number densities of 5-50 per sq.deg and magnitudes B < 19, 6dF is highly competitive for multi-object spectroscopy at low to medium dispersion. At present, however, it is not available for common-user non-survey spectroscopy, since all time on the UKST is devoted to the RAVE survey, which funds the operation of the telescope. Astronomers interested in the possible future use of 6dF for non-survey spectroscopy are invited to contact the AAO Director, Matthew Colless.
Page maintained by: Fred Watson, AAO
Latest revision: 19 Dec 2008