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arXiv · 1212.3615

Reconstructing the distribution of haloes and mock galaxies below the resolution limit in cosmological simulations

Sylvain de la Torre·John A. Peacock
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Abstract

We present a method for populating dark matter simulations with haloes of mass below the resolution limit. It is based on stochastically sampling a field derived from the density field of the halo catalogue, using constraints from the conditional halo mass function n(m|{\delta}). We test the accuracy of the method and show its application in the context of building mock galaxy samples. We find that this technique allows precise reproduction of the two-point statistics of galaxies in mock samples constructed with this method. Our results demonstrate that the full information content of a simulation can be communicated efficiently using only a catalogue of the more massive haloes.

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Sylvain de la Torre, John A. Peacock. 2012-12-14. Reconstructing the distribution of haloes and mock galaxies below the resolution limit in cosmological simulations. https://doi.org/10.1093/mnras%2Fstt1333

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