Federico Marulli, Marco Baldi, Lauro Moscardini
We investigate the spatial properties of the large scale structure (LSS) of
the Universe in the framework of coupled dark energy (cDE) cosmologies. Using
the public halo catalogues from the CoDECS simulations -- the largest set of
N-body experiments to date for such cosmological scenarios -- we estimate the
clustering and bias functions of cold dark matter (CDM) haloes, both in real-
and redshift-space. Moreover, we investigate the effects of the dark energy
(DE) coupling on the geometric and dynamic redshift-space distortions,
quantifying the difference with respect to the concordance LambdaCDM model. At
z~0, the spatial properties of CDM haloes in cDE models appear very similar to
the LambdaCDM case, even if the cDE models are normalized at last scattering in
order to be consistent with the latest Cosmic Microwave Background (CMB) data.
At higher redshifts, we find that the DE coupling produces a significant
scale-dependent suppression of the halo clustering and bias function. This
effect, that strongly depends on the coupling strength, is not degenerate with
sigma8 at scales r<5-10 Mpc/h. Moreover, we find that the coupled DE strongly
affects both the linear distortion parameter, beta, and the pairwise peculiar
velocity dispersion, sigma12. Although the models considered in this work are
found to be all in agreement with presently available observational data, the
next generation of galaxy surveys will be able to put strong constraints on the
level of coupling between DE and CDM exploiting the shape of redshift-space
clustering anisotropies.
View original:
http://arxiv.org/abs/1110.3045
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