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Evolution of the cluster abundance in non-Gaussian models

James Robinson·Jonathan E. Baker
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Abstract

We carry out N-body simulations of several non-Gaussian structure formation models, including Peebles' isocurvature cold dark matter model, cosmic string models, and a model with primordial voids. We compare the evolution of the cluster mass function in these simulations with that predicted by a modified version of the Press-Schechter formalism. We find that the Press-Schechter formula can accurately fit the cluster evolution over a wide range of redshifts for all of the models considered, with typical errors in the mass function of less than 25%, considerably smaller than the amount by which predictions for different models may differ. This work demonstrates that the Press-Schechter formalism can be used to place strong model independent constraints on non-Gaussianity in the universe.

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James Robinson, Jonathan E. Baker. 1999-05-08. Evolution of the cluster abundance in non-Gaussian models. https://doi.org/10.1046/j.1365-8711.2000.03109.x

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