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Hierarchical Object Formation in the Peculiar Velocity Field

H. Mouri·Y. Taniguchi
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Abstract

Using the initial peculiar velocity field, we analytically study the hierarchical formation of gravitationally bound objects. The field is smoothed over a scale that corresponds to the mass of a given class of objects. Through the Zel'dovich approximation, the smoothed field determines how the objects cluster together to form a new class of more massive objects. The standard cosmological parameters lead to the evolution of primordial clouds with 10^6 M(sun) -> galaxies with 10^12 M(sun) -> clusters of galaxies with 10^15 M(sun) -> superclusters of galaxies with 10^16 M(sun). The epochs obtained for the formation of these classes of objects are consistent with observations.

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H. Mouri, Y. Taniguchi. 2007-04-20. Hierarchical Object Formation in the Peculiar Velocity Field. https://doi.org/10.1086/491725

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