The influence of superstructures on bright galaxy environments:
  clustering properties
  We analyse the dependence of clustering properties of galaxies as a function
of their large-scale environment. In order to characterize the environment on
large scales, we use the catalogue of future virialized superstructures (FVS)
by Luparello et al. and separate samples of luminous galaxies according to
whether or not they belong to FVS. In order to avoid biases in the selection of
galaxies, we have constructed different subsamples so that the distributions of
luminosities and masses are comparable outside and within FVS. As expected, at
large scales, there is a strong difference between the clustering of galaxies
inside and outside FVS. However, this behaviour changes at scales r < 1 Mpc/h,
where the correlations have similar amplitudes. The amplitude of the two-halo
term of the correlation function for objects inside FVS does not depend on
their mass, but rather on that of the FVS. This is confirmed by comparing this
amplitude with that expected from extended Press-Schechter fits. In order to
compare these observational results with current models for structure
formation, we have performed a similar analysis using a semi-analytic
implementation in a LCDM cosmological model. We find that the cross-correlation
functions from the mock catalogue depend on the large-scale structures in a
similar way to the observations. From our analysis, we conclude that the
clustering of galaxies within the typical virialized regions of groups, mainly
depends on the halo mass, irrespective of the large-scale environment.
