Matter Power Spectrum Covariance Matrix from the DEUS-PUR ΛCDM simulations: Mass Resolution and non-Gaussian Errors

Abstract

The upcoming generation of galaxy surveys will probe the distribution of matter in the universe with unprecedented accuracy. Measurements of the matter power spectrum at different scales and redshifts will provide stringent constraints on the cosmological parameters. However, on non-linear scales this will require an accurate evaluation of the covariance matrix. Here, we compute the covariance matrix of the 3D matter density power spectrum for the concordance $\Lambda$CDM cosmology from an ensemble of N-body simulations of the Dark Energy Universe Simulation - Parallel Universe Runs (DEUS-PUR). This consists of 12288 realisations of a $(656h^{-1}\text{Mpc}{)}^3$ simulation box with $256^3$ particles. We combine this set with an auxiliary sample of 96 simulations of the same volume with $1024^3$ particles. We find N-body mass resolution effect to be an important source of systematic errors on the covariance at high redshift and small intermediate scales. We correct for this effect by introducing an empirical statistical method which provide an accurate determination of the covariance matrix over a wide range of scales including the Baryon Oscillations interval. Contrary to previous studies that used smaller N-body ensembles, we find the power spectrum distribution to significantly deviate from expectations of a Gaussian random density field at $k\gtrsim 0.25h{\text{Mpc}}^{-1}$ and $z<0.5$. This suggests that in the case of finite volume surveys an unbiased estimate of the ensemble averaged band power at these scales and redshifts may require a careful assessment of non-Gaussian errors more than previously considered.

arXiv comment9 pages, 8 figures, accepted for publication in MNRAS, covariance matrices available upon request to the authors

References in corpus (38)

• Wilkinson Microwave Anisotropy Probe (WMAP) Three Year Results: Implications for Cosmology
• Detection of the Baryon Acoustic Peak in the Large-Scale Correlation Function of SDSS Luminous Red Galaxies
• The 2dF Galaxy Redshift Survey: Power-spectrum analysis of the final dataset and cosmological implications
• Cosmological Hydrodynamics with Adaptive Mesh Refinement: a new high resolution code called RAMSES
• The Baryon Oscillation Spectroscopic Survey of SDSS-III
• The clustering of galaxies in the SDSS-III Baryon Oscillation Spectroscopic Survey: Baryon Acoustic Oscillations in the Data Release 10 and 11 galaxy samples
• The 3D power spectrum of galaxies from the SDSS
• LSST Science Book, Version 2.0
• Cosmology and fundamental physics with the Euclid satellite
• Why your model parameter confidences might be too optimistic -- unbiased estimation of the inverse covariance matrix
• The 2dF Galaxy Redshift Survey: The power spectrum and the matter content of the universe
• Measuring the Baryon Acoustic Oscillation scale using the SDSS and 2dFGRS
• Transients from Initial Conditions in Cosmological Simulations
• Scaling relations for galaxy clusters in the Millennium-XXL simulation
• Transients from Initial Conditions: A Perturbative Analysis
• The Coyote Universe I: Precision Determination of the Nonlinear Matter Power Spectrum
• Power Spectrum Correlations Induced by Non-Linear Clustering
• Putting the Precision in Precision Cosmology: How accurate should your data covariance matrix be?
• The detectability of baryonic acoustic oscillations in future galaxy surveys
• Simulations of Wide-Field Weak Lensing Surveys I: Basic Statistics and Non-Gaussian Effects
• Initial Conditions for Large Cosmological Simulations
• A simple multigrid scheme for solving the Poisson equation with arbitrary domain boundaries
• A New Algorithm for Computing Statistics of Weak Lensing by Large-Scale Structure
• MLAPM - a C code for cosmological simulations
• The Growth of Correlations in the Matter Power Spectrum
• Simulations of Baryon Acoustic Oscillations II: Covariance matrix of the matter power spectrum
• The New Horizon Run Cosmological N-Body Simulations
• Estimating Cosmological Parameter Covariance
• Dark Sky Simulations: Early Data Release
• Covariance of cross-correlations: towards efficient measures for large-scale structure
• Information content of the non-linear power spectrum: the effect of beat-coupling to large scales
• Cosmic variance of weak lensing surveys in the non-Gaussian regime
• Non-Gaussian Error Contribution to Likelihood Analysis of the Matter Power Spectrum
• Towards quantitative control on discreteness error in the non-linear regime of cosmological N body simulations
• Cosmic variance limited Baryon Acoustic Oscillations from the DEUS-FUR $\Lambda$CDM simulation
• Information Content in the Galaxy Angular Power Spectrum from the Sloan Digital Sky Survey and Its Implication on Weak Lensing Analysis
• Non-Gaussian errors of baryonic acoustic oscillations
• Simulating the Effect of Non-Linear Mode-Coupling in Cosmological Parameter Estimation

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