WMAP2006: Cosmological Parameters and Large-scale Structure of the Universe

TL;DR

This paper determines key cosmological parameters of the Lambda CDM model using WMAP three-year data and large-scale structure observations, confirming the model's consistency with various cosmic measurements.

Contribution

It provides updated best-fit cosmological parameters based on combined WMAP and large-scale structure data, and analyzes their agreement with observations.

Findings

LambdaCDM parameters are consistent with CMB and galaxy data

Model agrees well with power spectra of density perturbations

Discrepancies in some large-scale structure characteristics are discussed

Abstract

The parameters of cosmological model with cold dark matter and cosmological constant (Lambda CDM) have been determined on a basis of three-year cosmic microwave background observations by space mission WMAP, as well as the data on the large-scale structure of the Universe. The data cover scales from 1 up to 10000 Mpc. The best-fit values of LambdaCDM model parameters were found by minimization of chi^2 using the Levenberg-Markquardt approach (Omega_Lambda=0.736+-0.065, Omega_m=0.238+-0.080, Omega_b=0.05+-0.011, h=0.68+- 0.09, sigma_8=0.73+-0.08 and n_s=0.96+-0.015). It is shown that the LambdaCDM model with these values of the parameters agrees well with the angular power spectrum of cosmic microwave background and with power spectra of the density perturbations, estimated from spatial distributions of galaxies, rich galaxy clusters and from statistics of Ly_alpha absorption lines in spectra of distant quasars as well. The accordance of modeled characteristics of the large-scale structure with observable ones was analyzed, and possible reasons of significant discrepancies between some of them were considered.