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arXiv · 1307.2632

Imprint of primordial non-Gaussianity on dark matter halo profiles

Azadeh Moradinezhad Dizgah·Scott Dodelson·Antonio Riotto
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Abstract

We study the impact of primordial non-Gaussianity on the density profile of dark matter halos by using the semi-analytical model introduced recently by Dalal {\it et al.} which relates the peaks of the initial linear density field to the final density profile of dark matter halos. Models with primordial non-Gaussianity typically produce an initial density field that differs from that produced in Gaussian models. We use the path-integral formulation of excursion set theory to calculate the non-Gaussian corrections to the peak profile and derive the statistics of the peaks of non-Gaussian density field. In the context of the semi-analytic model for halo profiles, currently allowed values for primordial non-Gaussianity would increase the shapes of the inner dark matter profiles, but only at the sub-percent level except in the very innermost regions.

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Azadeh Moradinezhad Dizgah, Scott Dodelson, Antonio Riotto. 2013-07-10. Imprint of primordial non-Gaussianity on dark matter halo profiles. https://doi.org/10.1103/physrevd.88.063513

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