Radio and optical properties of double galaxies

An empirical study is made of the basic radio and optical properties of a large, well defined, complete sample of isolated pairs of galaxies. The selection criterion for this sample requires that these galaxies are in some of the sparsest regions of space. Because such representatives of the ''field'' population have recently been shown to be exceedingly rare, a survey of these galaxies allows a comprehensive study of the radio source phenomenon in regions of galaxy density as different from rich clusters as possible. Due to this selection criterion the sample is approximately 75% spirals