Large Scale Structures in the Las Campanas Redshift Survey and in Simulations

Abstract

The large supercluster structures obvious in recent galaxy redshift surveys are quantified using an one-dimensional cluster analysis (core sampling) and a three-dimensional cluster analysis based on the minimal spanning tree. The comparison with the LCRS reveals promising stable results. At a mean overdensity of about ten, the supercluster systems form huge wall-like structures comprising about 40% of all galaxies. The overdense clusters have a low mean transverse velocity dispersion of about 400 km/s, i.e. they look quite narrow in redshift space. We performed N-body simulations with large box sizes for six cosmological scenarios. The quantitative analysis shows that the observed structures can be understood best in low density models with $Ω_m \le 0.5$ with or without a cosmological constant.