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

It is possible to detect gravitationally-lensed quasars spectroscopically i f the spectra obtained during galaxy surveys are searched for the presence of quasar emission lines. The up-coming 6 degree Field (6dF) redshift surve y on the United Kingdom Schmidt Telescope will involve obtaining similar to 10(5) spectra of near-infrared selected galaxies to a magnitude limit of K = 13. Applying previously developed techniques implies that at least one l ens should be discovered in the 6dF survey, but that as many as ten could b e found if quasars typically have B-J - K similar or equal to 8. In this mo del there could be up to fifty lensed quasars in the, sample, but most of t hem could only be detected by infrared spectroscopy.