Lagrangian-space Gaussian ansatz for the matter redshift-space power spectrum and correlation function

Abstract

We study the predictions for the matter redshift-space power spectrum and correlation function of a Lagrangian-space Gaussian ansatz introduced in a previous work. This model is a natural extension of the Zeldovich approximation, where the displacement and velocity power spectra are determined by the equations of motion, instead of being set equal to the linear power spectrum. It does not contain any free parameter. As for the real-space statistics, we find that this Lagrangian-space approach is much more efficient for the correlation functions than for the power spectra. The damping of the BAO oscillations is well recovered but there is a large smooth drift from the simulations in the power spectra. The multipoles of the correlation functions are well recovered on BAO scales, with an accuracy of $2\%$ for ${\xi }_0^s$ down to $10h^{-1}$ Mpc, and of $3\%$ for ${\xi }_2^s$ down to $26h^{-1}$ Mpc, at $z\ge 0.35$.

15 pages

References in corpus (15)

• Five-Year Wilkinson Microwave Anisotropy Probe (WMAP) Observations: Cosmological Interpretation
• The Effective Field Theory of Cosmological Large Scale Structures
• Resumming Cosmological Perturbations via the Lagrangian Picture: One-loop Results in Real Space and in Redshift Space
• On the Robustness of the Acoustic Scale in the Low-Redshift Clustering of Matter
• The clustering of galaxies in the completed SDSS-III Baryon Oscillation Spectroscopic Survey: Observational systematics and baryon acoustic oscillations in the correlation function
• The IR-resummed Effective Field Theory of Large Scale Structures
• A critical look at cosmological perturbation theory techniques
• A 2.5% measurement of the growth rate from small-scale redshift space clustering of SDSS-III CMASS galaxies
• Multi-Point Propagators in Cosmological Gravitational Instability
• Large-N expansions applied to gravitational clustering
• Lagrangian perturbation theory at one loop order: successes, failures, and improvements
• Precision modeling of redshift-space distortions from multi-point propagator expansion
• Perturbation theory approach for the power spectrum: from dark matter in real space to massive haloes in redshift space
• Large-scale structure perturbation theory without losing stream crossing
• Projection of the gravitational dynamics on a subspace of probability distributions: curl-free Gaussian ansatz