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arXiv · 1501.00846

Effective Dark Matter Halo catalog in $f(R)$ gravity

Jian-hua He·Adam J. Hawken·Baojiu Li·Luigi Guzzo
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Abstract

We introduce the idea of {\it effective} dark matter halo catalog in $f(R)$ gravity, which is built using the {\it effective} density field. Using a suite of high resolution N-body simulations, we find that the dynamical properties of halos, such as the distribution of density, velocity dispersion, specific angular momentum and spin, in the effective catalog of $f(R)$ gravity closely mimic those in the $\Lambda$CDM model. Thus, when using effective halos, an $f(R)$ model can be viewed as a $\Lambda$CDM model. This effective catalog therefore provides a convenient way for studying the baryonic physics, the galaxy halo occupation distribution and even semi-analytical galaxy formation in $f(R)$ cosmologies.

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Jian-hua He, Adam J. Hawken, Baojiu Li, Luigi Guzzo. 2015-01-05. Effective Dark Matter Halo catalog in $f(R)$ gravity. https://doi.org/10.1103/physrevlett.115.071306

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