Skewness as a probe of Baryon Acoustic Oscillations

Abstract

In this study we show that the skewness S_3 of the cosmic density field contains a significant and potentially detectable and clean imprint of Baryonic Acoustic Oscillations. Although the BAO signal in the skewness has a lower amplitude than second order measures like the two-point correlation function and power spectrum, it has the advantage of a considerably lower sensitivity to systematic influences. Because it lacks a direct dependence on bias if this concerns simple linear bias, skewness will be considerably less beset by uncertainties due to galaxy bias. Also, it has a weaker sensitivity to redshift distortion effects. We use perturbation theory to evaluate the magnitude of the effect on the volume-average skewness, for various cosmological models. One important finding of our analysis is that the skewness BAO signal occurs at smaller scales than that in second order statistics. For an LCDM spectrum with WMAP7 normalization, the BAO feature has a maximum wiggle amplitude of ~3% and appears at a scale of ~82Mpc/h. We conclude that the detection of BAO wiggles in future extensive galaxy surveys via the skewness of the observed galaxy distribution may provide us with a useful, and potentially advantageous, measure of the nature of Dark Energy.

7 pages, 5 figures, accepted for publication in MNRAS, minor changes

References in corpus (13)

• Seven-Year Wilkinson Microwave Anisotropy Probe (WMAP) Observations: Cosmological Interpretation
• Dark Energy and the Accelerating Universe
• Cosmological Constraints from the SDSS Luminous Red Galaxies
• The WiggleZ Dark Energy Survey: Survey Design and First Data Release
• Nonlinear Evolution of Baryon Acoustic Oscillations
• Cosmology and the Bispectrum
• The Scale Dependence of Halo and Galaxy Bias: Effects in Real Space
• The detectability of baryonic acoustic oscillations in future galaxy surveys
• Measuring the matter density using baryon oscillations in the SDSS
• Systematic effects in the sound horizon scale measurements
• Statistical analysis of galaxy surveys - III: The non-linear clustering of red and blue galaxies in the 2dFGRS
• Higher-Order Angular Galaxy Correlations in the SDSS: Redshift and Color Dependence of non-Linear Bias
• Hierarchy of N-point functions in the LCDM and ReBEL cosmologies

Cited by in corpus (8)

• Testing the theory of gravity with DESI: estimators, predictions and simulation requirements
• Maximal compression of the redshift space galaxy power spectrum and bispectrum
• Hierarchical clustering in chameleon $f(R)$ gravity
• Revealing modified gravity signal in matter and halo hierarchical clustering
• Effects of Linear Redshift Space Distortions and Perturbation Theory on BAOs: A 3D Spherical Analysis
• Shell-like structures in our cosmic neighbourhood
• Bending the web: exploring the impact of modified gravity on the density field and halo properties within the cosmic web
• Anisotropic Counts-in-Cells in Redshift Space: A New Route to Cosmological Constraints from Galaxy Surveys