The Edinburgh-Cape Blue Object Survey – IV. Zone 3: Galactic latitudes −40° > b > −50°

Results for Zone 3 of the Edinburgh-Cape (EC) Blue Object survey are presented. This zone covers that part of the South Galactic Cap between 40° and 50° from the Galactic plane and south of about −12| .∘|3 of declination. EC Zone 3 contains 53 UK Schmidt Telescope fields covering about 1400 deg2 in which we find some 534 blue objects, including hot subdwarfs (∼39 per cent), white dwarfs (∼21 per cent), cataclysmic variables (∼2 per cent) and some star-like galaxies (∼9 per cent). A further 178 cooler stars observed in the survey, including low-metallicity F- and G-type stars, are also listed. Both low-dispersion spectroscopic classification and UBV photometry are presented for almost all of the hot objects and either spectroscopy or photometry (sometimes both) for the cooler ones.