Clustering, Angular Size and Dark Energy

R. C. Santos; J. A. S. Lima

doi:10.1103/physrevd.77.083505

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arXiv · 0803.1865

Clustering, Angular Size and Dark Energy

R. C. Santos·J. A. S. Lima

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Abstract

The influence of dark matter inhomogeneities on the angular size-redshift test is investigated for a large class of flat cosmological models driven by dark energy plus a cold dark matter component (XCDM model). The results are presented in two steps. First, the mass inhomogeneities are modeled by a generalized Zeldovich-Kantowski-Dyer-Roeder (ZKDR) distance which is characterized by a smoothness parameter $α(z)$ and a power index $γ$, and, second, we provide a statistical analysis to angular size data for a large sample of milliarcsecond compact radio sources. As a general result, we have found that the $α$ parameter is totally unconstrained by this sample of angular diameter data.

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R. C. Santos, J. A. S. Lima. 2008-03-12. Clustering, Angular Size and Dark Energy. https://doi.org/10.1103/physrevd.77.083505

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