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arXiv · 1801.02547

A new smooth-$k$ space filter approach to calculate halo abundances

Matteo Leo·Carlton M. Baugh·Baojiu Li·Silvia Pascoli
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Abstract

We propose a new filter, a smooth-$k$ space filter, to use in the Press-Schechter approach to model the dark matter halo mass function which overcomes shortcomings of other filters. We test this against the mass function measured in N-body simulations. We find that the commonly used sharp-$k$ filter fails to reproduce the behaviour of the halo mass function at low masses measured from simulations of models with a sharp truncation in the linear power spectrum. We show that the predictions with our new filter agree with the simulation results over a wider range of halo masses for both damped and undamped power spectra than is the case with the sharp-$k$ and real-space top-hat filters.

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Matteo Leo, Carlton M. Baugh, Baojiu Li, Silvia Pascoli. 2018-01-08. A new smooth-$k$ space filter approach to calculate halo abundances. https://doi.org/10.1088/1475-7516%2F2018%2F04%2F010

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