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arXiv · 0812.1052

The Coyote Universe I: Precision Determination of the Nonlinear Matter Power Spectrum

Katrin Heitmann·Martin White·Christian Wagner·Salman Habib·David Higdon
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Abstract

Near-future cosmological observations targeted at investigations of dark energy pose stringent requirements on the accuracy of theoretical predictions for the clustering of matter. Currently, N-body simulations comprise the only viable approach to this problem. In this paper we demonstrate that N-body simulations can indeed be sufficiently controlled to fulfill these requirements for the needs of ongoing and near-future weak lensing surveys. By performing a large suite of cosmological simulation comparison and convergence tests we show that results for the nonlinear matter power spectrum can be obtained at 1% accuracy out to k~1 h/Mpc. The key components of these high accuracy simulations are: precise initial conditions, very large simulation volumes, sufficient mass resolution, and accurate time stepping. This paper is the first in a series of three, with the final aim to provide a high-accuracy prediction scheme for the nonlinear matter power spectrum.

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Katrin Heitmann, Martin White, Christian Wagner, Salman Habib, David Higdon. 2010-08-24. The Coyote Universe I: Precision Determination of the Nonlinear Matter Power Spectrum. https://doi.org/10.1088/0004-637x/715/1/104

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