We investigated the structures on scales beyond the typical clusters of galaxies. These structures are crucial to understand the cosmic gravitational clustering in the pre-virialized stage, or quasilinear r\`egime. Based on the multi-resolution analysis of the discrete wavelet transformation, we got statistical available ensembles of $r_{ cl}$-clusters, i.e. the structures on scale $r_{ cl}$, in the range $1 \leq r_{ cl} \leq 24 h^{ -1}$ Mpc for both N-body simulation and the IRAS 1.2 Jy galaxy survey samples. If the mass-to-light ratio on scales larger than clusters asymptotically reaches a constant, we found that the abundances and correlations of these IRAS $r_{ cl}$-clusters to be basically consistent with the predictions of the flat low-density CDM model (LCDM) and the open CDM model (OCDM), except the model-predicted abundance of $r_{ cl} = 24 h^{ -1}$ Mpc clusters seems to be higher than IRAS data. The standard CDM (SCDM) gives too much power, and too weak correlations on all the scales. For a given $r_{ cl}$, the amplitude of two-point correlation function of $r_{ cl}$-clusters is increasing with their richness. However, for a given richness (defined by the mean separation of neighbor objects), the clustering strengths of both simulation and observation sample are found to be declining with $r_{ cl}$ when $r_{ cl}$ is larger than 3 - 4 $h^{ -1}$ Mpc. Therefore, the ``universal'' increase of the correlation amplitude with the scale of objects from galaxies, groups, to poor, rich clusters is broken down for structures of $r_{ cl} > 3 - 4 h^{ -1}$ Mpc. Supercluster should not be a member of the ``universal'' increase family.

Categories: astro-ph

Abundances and Correlations of Structures Beyond Galaxy Clusters