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arXiv · 1604.02147

Achieving Convergence in Galaxy Formation Models by Augmenting N-body Merger Trees

Andrew J. Benson·Chris Cannella·Shaun Cole
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Abstract

Accurate modeling of galaxy formation in a hierarchical, cold dark matter universe requires the use of sufficiently high-resolution merger trees to obtain convergence in the predicted properties of galaxies. When semi-analytic galaxy formation models are applied to cosmological N-body simulation merger trees, it is often the case that those trees have insufficient resolution to give converged galaxy properties. We demonstrate a method to augment the resolution of N-body merger trees by grafting in branches of Monte Carlo merger trees with higher resolution, but which are consistent with the pre-existing branches in the N-body tree. We show that this approach leads to converged galaxy properties.

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Andrew J. Benson, Chris Cannella, Shaun Cole. 2016-04-07. Achieving Convergence in Galaxy Formation Models by Augmenting N-body Merger Trees. https://arxiv.org/abs/1604.02147

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