The Coyote Universe. I. Precision Determination of the Nonlinear Matter Power Spectrum
Abstract
Near-future cosmological observations targeted at investigations of dark energy pose stringent requirements on the accuracy of theoretical predictions for the nonlinear clustering of matter. Currently, N-body simulations comprise the only viable approach to this problem. In this paper, we study various sources of computational error and methods to control them. By applying our methodology to a large suite of cosmological simulations we show that results for the (gravity-only) nonlinear matter power spectrum can be obtained at 1% accuracy out to k ~ 1 h Mpc-1. 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; the final aim is a high-accuracy prediction scheme for the nonlinear matter power spectrum that improves current fitting formulae by an order of magnitude.
- Publication:
-
The Astrophysical Journal
- Pub Date:
- May 2010
- DOI:
- 10.1088/0004-637X/715/1/104
- arXiv:
- arXiv:0812.1052
- Bibcode:
- 2010ApJ...715..104H
- Keywords:
-
- large-scale structure of universe;
- methods: numerical;
- Astrophysics
- E-Print:
- 18 pages, 22 figures, minor changes to address referee report