A Redshift Survey of Very Faint (B ≤ 22.5) Field Galaxies, Radio Sources, and Quasars

Abstract

As part of a three year program to study the evolution of galaxies, quasars, and radio sources (in collaborations with R. Kron and R. Windhorst), we will use over 30 nights on the KPNO 4-m CCD Cryogenic Camera System, in the multi-aperture mode, to measure the redshifts of several hundred very faint objects. These will be selected from four fields (SA68 00h+15; Lynx 08h+45; SA57 13h+30; Here 17h+50); for each we possess 4-m plates in four bandpasses (limits: U≃23, B≃24, V≃23, I≃21) as well as Westerbork interferometer maps to 1 mJy at 21cm (a 50cm survey is in progress). Galaxies are selected randomly by their apparent red magnitudes as measured with a PDS; quasar candidates to B≈22.5 by stellar objects which lie apart from Galactic stars in the multi-color diagram; and radio sources by their positional coincidence with optical images (~50% of the 300 radio sources are identified). To date, 10 nights have produced spectra of ∿250 field galaxies, ~20 radio sources, and ~40 quasar candidates.