Third-Order Density Perturbation and One-Loop Power Spectrum in Dark-Energy-Dominated Universe

Abstract

We investigate the third-order density perturbation and the one-loop correction to the linear power spectrum in the dark-energy cosmological model. Our main interest is to understand the dark-energy effect on baryon acoustic oscillations in a quasi-nonlinear regime ($k\approx 0.1h$/Mpc). Analytical solutions and simple fitting formulae are presented for the dark-energy model with the general time-varying equation of state $w(a)$. It turns out that the power spectrum coincides with the approximate result based on the EdS (Einstein de-Sitter) model within 1% for $k<0.4h/$Mpc at $z=0$ in the WMAP (Wilkinson Microwave Anisotropy Probe) 5yr best-fitting cosmological model, which suggests that the cosmological dependence is very small.

11 pages, Prog. Ther. Phys. in press, minor changes, references added

References in corpus (5)

• Five-Year Wilkinson Microwave Anisotropy Probe (WMAP) Observations: Cosmological Interpretation
• Measuring the Baryon Acoustic Oscillation scale using the SDSS and 2dFGRS
• WMAP constraints on low redshift evolution of dark energy
• Non-linear structure formation and the acoustic scale
• Perturbation Theory Reloaded II: Non-linear Bias, Baryon Acoustic Oscillations and Millennium Simulation In Real Space

Cited by in corpus (3)

• Simulations of Baryon Acoustic Oscillations II: Covariance matrix of the matter power spectrum
• Third-order Perturbation Theory With Non-linear Pressure
• Chasing the non-linear evolution of matter power spectrum with numerical resummation method: solution of closure equations