Statistical characteristics of simulated walls

Abstract

Accepted 2000 May 1. Received 2000 March 17; in original form 1999 July 14 ABSTRA C T The large-scale matter distribution in three different simulations of CDM models is investigated and compared with corresponding results of the Zel’dovich theory of non-linear gravitational instability. We show that the basic characteristics of wall-like structure elements are well described by this theory, and that they can be expressed by the cosmological parameters and a few spectral moments of the perturbation spectrum. Therefore the characteristics of such elements provide reasonable estimates of these parameters. We show that the compressed matter is relaxed and gravitationally confined and manifests itself in the existence of walls as (quasi-)stationary structure elements with a lifetime restricted by their disruption into high-density clouds. The matter distribution is investigated in both real and redshift spaces. In both cases almost the same particles form the walls, and we estimate differences in corresponding wall characteristics. The same methods are applied to several mock catalogues of ‘galaxies’, which allows us to characterize a large-scale bias between the spatial distribution of dark matter and of simulated ‘galaxies’.