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On the Dynamical Origin of Bias in Clusters of Galaxies

S. Colafrancesco·V. Antonuccio-Delogu·A. Del Popolo
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Abstract

We study the effect of the dynamical friction induced by the presence of substructure on the statistics of the collapse of density peaks. Applying the results of a former paper we show that within high density environments, like rich clusters of galaxies, the collapse of smaller peaks is strongly delayed until very late epochs. A bias of dynamical nature thus naturally arises because high density peaks preferentially collapse For a standard CDM model we find that this dynamical bias can account for a substantial part of the total bias required by observations on cluster scales.

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S. Colafrancesco, V. Antonuccio-Delogu, A. Del Popolo. 1994-10-29. On the Dynamical Origin of Bias in Clusters of Galaxies. https://doi.org/10.1086/176552

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