THE OPTICAL REDSHIFT SURVEY: SAMPLE SELECTION AND THE GALAXY DISTRIBUTION

摘要

This is the first in a series of papers describing the Optical Redshift Survey (ORS), a redshift survey of optically selected galaxies covering 98% of the sky above |b| =20° (8.09 sr). The survey is drawn from the Uppsala Galaxy Catalogue (UGC), the European Southern Observatory Galaxy Catalogue (ESO), and the Extension to the Southern Galaxy Catalogue (ESGC), and it contains two subcatalogs, one complete to a B magnitude of 14.5, the other complete to a B major axis diameter of 1.9′. The entire sample consists of 8457 objects, of which redshifts are now available for 8286; 171 objects remain without measured redshifts. Roughly 1300 of the redshifts were measured for the completion of the sample; the remainder were taken from the literature. Most of these new redshifts are concentrated at low Galactic latitudes, 20° ≤ |b| ≤ 30°, and within the strip not covered by either the UGC or ESO catalogues: -17.5° ≤ δ ≤ -2.5°. The ORS provides the most detailed and homogeneous sampling of the large-scale galaxy distribution to date in these areas. The density field of bright optical galaxies is well denned to 8000 km s~(-1) and is dominated by the Virgo, Hydra-Centaurus, Pisces-Perseus, Coma-A1367, and Telescopium-Pavo-Indus superclusters. The dense sampling provided by ORS allows a detailed analysis of the galaxy density field and will be used to test its dependence on morphology and other galaxy parameters.