Nonlinear evolution of baryon acoustic oscillations from improved perturbation theory in real and redshift spaces

Journal Article · Tue Dec 15 04:00:00 EST 2009 · Physical Review. D, Particles Fields

DOI:https://doi.org/10.1103/PHYSREVD.80.123503· OSTI ID:21313558

Taruya, Atsushi ^[1]; Nishimichi, Takahiro; Saito, Shun ^[2]; Hiramatsu, Takashi ^[3]

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1. Research Center for the Early Universe, School of Science, University of Tokyo, Bunkyo-ku, Tokyo 113-0033 (Japan)
2. Department of Physics, University of Tokyo, 113-0033 (Japan)
3. Institute for Cosmic Ray Research, University of Tokyo, Kashiwa, Chiba 277-8582 (Japan)

We study the nonlinear evolution of baryon acoustic oscillations in the matter power spectrum and correlation function from the improved perturbation theory (PT). Based on the framework of renormalized PT, which provides a nonperturbative way to treat the gravitational clustering of large-scale structure, we apply the closure approximation that truncates the infinite series of loop contributions at one-loop order, and obtain a closed set of integral equations for power spectrum and nonlinear propagator. The resultant integral expressions are basically equivalent to those previously derived in the form of evolution equations, and they keep important nonperturbative properties which can dramatically improve the prediction of nonlinear power spectrum. Employing the Born approximation, we then derive the analytic expressions for nonlinear power spectrum and the predictions are made for nonlinear evolution of baryon acoustic oscillations in power spectrum and correlation function. We find that the improved PT possesses a better convergence property compared with standard PT calculation. A detailed comparison between improved PT results and N-body simulations shows that a percent-level agreement is achieved in a certain range in power spectrum and in a rather wider range in correlation function. Combining a model of nonlinear redshift-space distortion, we also evaluate the power spectrum and correlation function in redshift space. In contrast to the results in real space, the agreement between N-body simulations and improved PT predictions tends to be worse, and a more elaborate modeling for redshift-space distortion needs to be developed. Nevertheless, with the currently existing model, we find that the prediction of correlation function has a sufficient accuracy compared with the cosmic-variance errors for future galaxy surveys with volume of a few h{sup -3} Gpc{sup 3} at z > or approx. 0.5.

• OSTI ID: 21313558
• Journal Information: Physical Review. D, Particles Fields, Journal Name: Physical Review. D, Particles Fields Journal Issue: 12 Vol. 80; ISSN PRVDAQ; ISSN 0556-2821
• Country of Publication: United States
• Language: English

Related Subjects

71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
79 ASTRONOMY AND ASTROPHYSICS
ACCURACY
BARYONS
BORN APPROXIMATION
COMPARATIVE EVALUATIONS
CONVERGENCE
CORRELATION FUNCTIONS
EVOLUTION
FORECASTING
GALAXIES
MATTER
NONLINEAR PROBLEMS
OSCILLATIONS
PERTURBATION THEORY
PROPAGATOR
RED SHIFT
SIMULATION
SPACE
SPECTRA