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Cluster-Galaxy Correlations in CDM Models

M. E. Merchan·M. G. Abadi·D. G. Lambas·C. A. Valotto
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Abstract

We study the ability of COBE-normalized CDM models to reproduce observed properties of the distribution of galaxies and clusters using N-body numerical simulations. We analyze the galaxy-galaxy and cluster-galaxy two-point correlation functions, $ξ_{gg}$ and $ξ_{cg}$, in open ($Ω_{0}=0.4, Ω_Λ=0, σ_8=0.75$), and flat ($Ω_{0}=0.3, Ω_Λ=0.7, σ_8=1.05$) CDM models which both reproduce the observed abundances of rich clusters of galaxies. To compare models with observations we compute projected cross-correlation functions $ω_{gg}$ and $ω_{cg}$ to derive the corresponding $ξ_{gg}$ and $ξ_{cg}$. We use target galaxies selected from Las Campanas Redshift Survey, target clusters selected from the APM Cluster Survey and tracer galaxies from the Edinburgh Durham Sky Survey catalog.

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M. E. Merchan, M. G. Abadi, D. G. Lambas, C. A. Valotto. 1997-11-20. Cluster-Galaxy Correlations in CDM Models. https://doi.org/10.1086/305453

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