An efficient hybrid method to produce high-resolution large-volume dark matter simulations for semi-analytic models of reionization

Abstract

Resolving faint galaxies in large volumes is critical for accurate cosmic reionization simulations. While less demanding than hydrodynamical simulations, semi-analytic reionization models still require very large N-body simulations in order to resolve the atomic cooling limit across the whole reionization history within box sizes ≳100 h−1 Mpc. To facilitate this, we extend the mass resolution of N-body simulations using a Monte Carlo algorithm. We also propose a method to evolve positions of Monte Carlo haloes, which can be an input for semi-analytic reionization models. To illustrate, we present an extended halo catalogue that reaches a mass resolution of Mhalo = 3.2 × 107 h−1 M☉ in a 105 h..