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Using the 6dF galaxy redshift survey to detect gravitationally-lensed quasars

Daniel J. Mortlock·Michael J. Drinkwater
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Abstract

It is possible to detect gravitationally-lensed quasars spectroscopically if the spectra obtained during galaxy surveys are searched for the presence of quasar emission lines. The up-coming 6 degree Field (6dF) redshift survey on the United Kingdom Schmidt Telescope (UKST) will involve obtaining 10^5 spectra of near-infrared selected galaxies to a magnitude limit of K = 13. Applying previously developed techniques implies that at least one lens should be discovered in the 6dF survey, but that as many as ten could be found if quasars typically have B_J - K = 8. In this model there could be up to fifty lensed quasars in the sample, but most of them could only be detected by infrared spectroscopy.

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Daniel J. Mortlock, Michael J. Drinkwater. 2001-03-14. Using the 6dF galaxy redshift survey to detect gravitationally-lensed quasars. https://doi.org/10.1071/as01023

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