The Canada-France Redshift Survey. I. Introduction to the Survey, Photometric Catalogs, and Surface Brightness Selection Effects

The Canada-France Redshift Survey has been undertaken to provide a large well-defined sample of faint galaxies at high redshift in which the selection criteria match as closely as possible those of samples of nearby galaxies. The survey is designed to have a median redshift of z ∼ 0.6 corresponding to a look-back time of half the present age of the universe for Ω ∼ 1. Such a survey can then be used for studying many different aspects of the evolution of galaxies over the interval 0 < z < 1. In this paper we describe the selection of the fields, the multicolor imaging observations, and the construction and validation of the photometric catalogs. Particular attention is paid to quantifying the unavoidable selection effects in surface brightness, and their impact on the survey is assessed in the context of the properties of known populations of galaxies. The photometric catalogs contain several thousand objects brighter than I_AB ≤ 22.5 and are essentially complete for central surface brightnesses as faint as μ_AB(I) ∼ 24.5 mag arcsec^-2. This should be sufficient to include both normal surface brightness galaxies and prototypes of extreme low surface brightness galaxies.