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Evolution of galaxy clusters in $Λ$MDM cosmologies

N. A. Arkhipova·T. Kahniashvili·V. N. Lukash
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Abstract

The time evolution of galaxy cluster abundance is used to constrain cosmological parameters in dark matter models containing a fraction of hot particles (massive neutrino). We test the modified MDM models with cosmic gravitational waves which are in agreement with observational data at $z=0$, and show that they do not pass the cluster evolution test and therefore should be ruled out. The models with a non-zero cosmological constant are in better agreement with the evolution test. We estimate $Ω_Λ$ and find that it is strongly affected by a small fraction of hot dark matter: $0.4 <Ω_Λ<0.8$ for $Ω_H /Ω_M <0.2$.

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N. A. Arkhipova, T. Kahniashvili, V. N. Lukash. 2001-06-29. Evolution of galaxy clusters in $Λ$MDM cosmologies. https://arxiv.org/abs/astro-ph/0106559

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