THE SPATIAL-DISTRIBUTION OF BLUE COMPACT GALAXIES IN THE 2ND BYURAKAN SURVEY

We present the results of a study of the spatial distribution relative to bright normal galaxies of a new large sample of blue compact galaxies (BCGs) in the zone of the Second Byurakan Survey (SBS): 7(h)40(m) less than or equal to a less than or equal to 17(h)20(m), 40 degrees less than or equal to delta less than or equal to 61.2 degrees, using as statistic the distance D-NN to the nearest neighboring bright galaxy. We-found that the majority (similar to 80%) of BCGs have D-NN < 5 h(-1) Mpc and follow generally the large-scale structure delineated by bright galaxies, but that a minority (similar to 20%) have D-NN > 5 h(-1) Mpc and are found in voids. The large deficiency of BCGs with D-NN less than or similar to 2 h(-1) Mpc supports the hypothesis that the majority of dwarf galaxies originate as low-mass primordial density fluctuations, but not as debris resulting from tidal interactions between massive galaxies. The spatial distribution of BCGs is consistent with that found for low-surface-brightness dwarfs, supporting the idea that BCGs are LSB dwarfs undergoing intense bursts of star formation.