Possible Connexion Between Large Scale Structures

Abstract

From the Lyon-Meudon Extragalactic Database LEDA, we constructed a sample of 27,000 galaxies with radial velocities smaller than 15,000 km s$^{-1}$. From this first sample we selected the 5,683 largest galaxies which constitute a sample complete up to the diameter limit $D_{25}=1.6'$. This sub-sample has been used to search for the most populated plane. The result is that the plane defined by the pole ($l=52 °$; $b=16 °$) contains twice as many galaxies as would be found for randomly distributed galaxies. This plane is not far from the supergalactic plane. Then, the distribution of galaxies is studied in this plane by using the radial velocity as an estimate of the distance. An excess of galaxies appears at a distance of about 70 Mpc. We discuss the reality of this density enhancement which could result from selection effects.